Topical formulations of tellurium-containing compounds

ABSTRACT

Novel formulations of tellurium-containing compounds, which are suitable for topical application, are disclosed. The formulations are characterized by high chemical and physical stability and are easy to handle and use.

RELATED APPLICATIONS

This Application is a National Phase of PCT Patent Application No.PCT/IB2007/004220 having International filing date of Sep. 10, 2007,which claims the benefit of U.S. Provisional Patent Application No.60/843,402 filed on Sep. 11, 2006. The contents of the aboveApplications are all incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to novel formulations oftellurium-containing compounds and particularly to tellurium-containingformulations that are designed for topical application. The novelformulations of tellurium-containing compounds of the present inventionare characterized by chemical and physical stability, which isapplicable when the tellurium-containing compounds are present thereinin low, as well as in high, and very high concentrations.

2. Description of the Related Art

Various tellurium-containing compounds have been described in the art ashaving therapeutic activity. A particularly effective family oftellurium-containing compounds is taught, for example, in U.S. Pat. Nos.4,752,614; 4,761,490; 4,764,461 and 4,929,739, whereby another effectivefamily is taught, for example, in PCT International Patent ApplicationNo. PCT/IL2005/000989, which are all incorporated by reference as iffully set forth herein.

One of the most promising compounds described in these patents isammonium trichloro(dioxyethylene-O,O′)tellurate, which is also referredto herein and in the art as AS101. AS101, as a representative example ofthe family of tellurium-containing compounds discussed hereinabove,exhibits antiviral (Nat. Immun. Cell Growth Regul. 7(3):163-8, 1988,AIDSRes Hum Retroviruses. 8(5):613-23, 1992), and tumoricidal activity(Nature 330(6144): 173-6, 1987; J. Clin. Oncol. 13(9):2342-53, 1995; J.Immunol. 161(7):3536-42, 1998).

Another promising tellurium-containing compound is [TeO₄(COCHH)₂]₂,which is also referred to herein and in the art as SAS.

SAS and other ditellurium-containing compounds have been shown to act aseffective inhibitors of caspase-1/interleukin-1β enzyme b (ICE) andtheir use in various additional therapeutic applications have also beendescribed (see, for example, PCT/IL2005/000989 supra).

It has been suggested that AS101, SAS, and other tellurium-containingcompounds, act as immunomodulators that stimulate the innate andacquired arm of the immune response. For example, it has been shown thatAS101 is a potent activator of interferon (IFN) in mice (J. Natl. CancerInst. 88(18):1276-84, 1996) and in humans (Nat. Immun. Cell GrowthRegul. 9(3):182-90, 1990; Immunology 70(4):473-7, 1990; J. Natl. CancerInst. 88(18):1276-84, 1996). It has also been demonstrated that AS101,as well as other tellurium-containing immunomodulators, induce thesecretion of a spectrum of cytokines, such as IL-1α, IL-6 and TNF-α, andthat macrophages are one main target for AS101 (Exp. Hematol.23(13):1358-66, 1995). It was further found that AS101 inhibits IL-10 atthe m-RNA level, and that this inhibition may cause an increase in IL-12and IFN-γ (Cell Immunol. 176(2):180-5, 1997; J. Natl. Cancer Inst88(18):1276-84, 1996).

Use of tellurium-containing compounds, such as AS101 and SAS, fortreating conditions in which inhibition of ICE is beneficial has alsobeen shown (see, for example, International Patent Application Nos.PCT/IL2005/000990 and PCT/IL2005/000989, supra). In another example,tellurium-containing compounds, in particular AS101, were shown to havea stimulating effect on bone marrow cells (U.S. Pat. No. 4,946,437).

Tellurium-containing compounds, in particular AS101, are further knownto treat or prevent gastritis or peptic ulcer (U.S. Pat. No. 5,576,347),and to treat or prevent babesiosis, a tick-born disease (U.S. Pat. No.5,610,179). AS101 has also been shown to have protective effects againstlethal and sublethal effects of irradiation and chemotherapy (Blood 85:1555, 1995; J. Nat. Cancer Inst. 88: 1276, 1996; In. J. Cancer 86: 281,2000; J. Immunol. 156: 1101, 1996; J. Immunol. 145: 1507, 1990; CancerRes. 51: 1499, 1991).

Additional examples of medical conditions that are treatable by AS101and other tellurium-containing compounds are described, for example, inWO 2005/069735, U.S. Provisional Patent Application Nos. 60/716,924,60/716,923, 60/610,660, in PCT International Application No.PCT/IL2005/000992, in WO 2005/060341, in U.S. patent application Ser.No. 11/226,375 and in U.S. Pat. Nos. 4,752,614, 4,761,490, 4,764,461 and4,929,739 (supra).

Exemplary medical conditions that are known to be treatable by AS101 andother tellurium-containing compounds therefore include, for example,IL-1 mediated diseases, inflammatory diseases, autoimmune diseases,destructive bone disorders, proliferative disorders, infectiousdiseases, degenerative diseases, diseases associated with cell death, anexcess dietary alcohol intake disease, retinal disorders, uveitis,inflammatory peritonitis, osteoarthritis, pancreatitis, asthma, adultrespiratory distress syndrome, glomerulonephritis, rheumatoid arthritis,scleroderma, chronic thyroiditis, Grave's disease, autoimmune gastritis,diabetes, autoimmune hemolytic anemia, autoimmune neutropenia,thrombocytopenia, chronic active hepatitis, myasthenia gravis,inflammatory bowel disease, Crohn's disease, psoriasis, atopicdermatitis, scarring, human papilloma virus related skin and mucosalmembrane ailments, papilloma, condilloma, warts, alopecia and otherconditions associated with hair loss, graft versus host disease, organtransplant rejection, organ apoptosis after burn injury, osteoporosis,leukemia's and related disorders, myelodysplastic syndrome, multiplemyeloma-related bone disorders, acute myelogenous leukemia, chronicmyelogenous leukemia, metastatic melanoma, basal cell carcinoma, actinickeratosis, UV skin damage, irradiation and chemotherapy-related effects,Kaposi's sarcoma, multiple myeloma, hemorrhagic shock, sepsis, septicshock, burns, Shigellosis, Alzheimer's disease, Huntington's disease,Kennedy's disease, prion diseases, cerebral ischemia, epilepsy,myocardial ischemia, acute and chronic heart diseases, myocardialinfarction, congestive heart failure, atherosclerosis, coronary arterybypass graft, spinal muscular atrophy, amyotrophic lateral sclerosis,multiple sclerosis, HIV-related encephalitis, aging, neurological damagedue to stroke, ulcerative colitis, peptic ulcer, traumatic brain injury,spinal cord injury, hepatitis-B, hepatitis-C, hepatitis-G, yellow fever,dengue fever, or Japanese encephalitis, various forms of liver disease,renal disease, polycystic kidney disease, H. pylori-associated gastricand duodenal ulcer disease, HIV infection, tuberculosis, immunotherapyfor the treatment of various forms of cancer, babesiosis, organ failure,meningitis and complications associated with coronary artery bypassgrafts.

AS101 is also characterized by low toxicity, with the LD₅₀ values inrats following intravenous and intramuscular administration of AS101 are500-1000 folds higher than the immunologically effective dose. AS101 istherefore considered as an attractive therapeutically active agent.

Topical application of tellurium-containing compounds and pharmaceuticalcompositions thereof, has been found effective in the treatment ofvarious skin-related diseases and disorders.

Thus, tellurium-containing compounds were found exceptionally effectivein treating skin and mucosal membrane ailments, caused by humanpapilloma viruses (HPV) (see, for example WO 2005/069735, supra). HPV isa very common virus that causes abnormal cells or growth of tissue onthe skin of the body, thus causing abnormal tissue changes on the feet,hands, vocal cords, mouth and genital (sex) organs.

Another topical use of tellurium-containing compounds is in thetreatment or prevention of alopecia and other conditions associated withhair loss (see for example, U.S. Provisional Patent Application No.60/610,660, supra, U.S. Pat. Nos. 6,552,089 and 5,262,149). In humanclinical studies (FASEB J 18: 400-402, 2004), AS101 exhibited theability to protect cancer patients from both bone marrow toxicity andalopecia induced by chemotherapy. AS101 has been found to induce hairgrowth in nude mice, normal mice, and in humans. In nude mice, AS101 hasbeen shown to exert this effect when applied systemically, orally ortopically.

Other skin conditions which may be treated by topical application oftellurium-containing compounds, include basal cell carcinoma (BCC),actinic keratosis (AK) (U.S. Provisional Patent Application No.60/716,923, supra), damages caused by exposure to UV irradiation (U.S.Provisional Patent Application No. 60/716,924, supra), psoriasis (U.S.Pat. No. 6,472,381), atopic dermatitis (also known as eczema), Kaposi'ssarcoma, scleroderma, burns, scarring (see U.S. Provisional PatentApplication No. 60/610,660) and metastatic melanoma (Sun et al.“Anticarcinoma activity of a novel drug,3-ethyl-3′-methyl-thiatelluracarbocyanine iodide (Te), atellurium-containing cyanine targeted at mitochondria”, Clinical CancerResearch, 1996, Vol. 2, Issue 8, 1335-1340).

As is widely recognized in the art, pharmaceutical compositions fortopical application typically include a relatively large concentrationof the applied active ingredient.

While studying the features required for a tellurium-containing compoundto exhibit a therapeutic activity, it has been found that organic andinorganic tellurium-containing compounds that are derived from telluriumdioxide and hence have one or more tellurium dioxo moieties are highlypotent as therapeutically active agents.

Such tellurium-containing compounds are known to exhibit an oxidativepotential and, under certain conditions, may be considered unstable,both physically and chemically. When formulated into pharmaceuticalcompositions, and particularly for topical application, in which theirconcentration is relatively high, compounds containing tellurium dioxomoieties may be involved in oxidation and other reactions, which maylead, for example, to coloration of the pharmaceutical composition,degradation of various components therein, and/or incompatibility withcertain packaging materials. A particular disadvantage of such telluriumdioxo-containing compounds is seen when compositions containing same arepackaged, or come in other contact, with metallic substances. Metalssuch as aluminum are rapidly oxidized by these compounds. Therefore, todate, tellurium-containing pharmaceutical compositions, which areintended for topical application, often include relatively lowconcentrations of the active ingredient.

Additional limitations associated with formulating activetellurium-containing compounds into compositions for topical applicationresults from the relatively poor solubility of compounds such as AS 101and SAS in aqueous or oleaginous carriers. While some topicalformulations are based on oils and other hydrophobic carriers,formulations that are based on aqueous or amphiphilic carriers arebeneficially characterized by usage convenience, being easily applied,non-greasy, and particularly washable.

Pharmaceutical compositions of tellurium-containing compounds andvarious carriers have been described, for example, in InternationalPatent Application Nos. PCT/IL2005/000990 and PCT/IL2005/000989 and U.S.Pat. Nos. 4,752,614; 4,761,490, 4,764,461 and 4,929,739 (supra). Amongstthe various carriers cited therein, carriers comprising polyethyleneglycol (PEG) have been mentioned in passing. However, the applicabilityof PEG-based tellurium-containing formulations for topical uses, as wellas the chemical and physical stability of such formulations, have neverbeen established nor practiced heretofore.

In view of the exceptional therapeutic characteristics oftellurium-containing compounds which are derived from tellurium dioxideand hence have one or more tellurium dioxo moieties, describedhereinabove, there is a widely recognized need for, and it would behighly advantageous to have, stable tellurium-containing formulationsfor topical application.

SUMMARY OF THE INVENTION

One aspect of the present invention provides a formulation for topicalapplication comprising a tellurium-containing compound having at leastone tellurium dioxo moiety and a pharmaceutically acceptable carrier,the carrier being selected such that:

-   -   the tellurium-containing compound, at a concentration of 10        weight percents, is soluble, dispersible and/or suspendable        therein; and    -   the formulation is chemically and physically stable upon storage        at room temperature for at least 30 days.

Another aspect of the present invention provides a formulation fortopical application comprising a tellurium-containing compound in anamount up to about 25 weight percent and having at least one telluriumdioxo moiety and a pharmaceutically acceptable carrier, said carrierbeing selected such that:

said tellurium-containing compound, at a concentration of 10 weightpercents, is soluble, dispersible and/or suspendable therein; and

the formulation is chemically and physically stable upon storage at roomtemperature for at least 30 days.

According to further features in the preferred embodiments of theinvention described below, one or more carriers is selected such thatthe formulation is stable upon storage for at least 6 months at roomtemperature.

According to still further features in the described preferredembodiments the carrier is selected such that the formulation is stableupon storage at 40° C. for at least 30 days.

According to still further features in the described preferredembodiments the carrier is selected such that the formulation is stableupon storage at 40° C. for at least 60 days.

According to still further features in the described preferredembodiments the carrier is selected such that the formulation is stableupon storage at 40° C. for at least 90 days.

According to still further features in the described preferredembodiments the carrier is selected such that the formulation is stableupon cycling at a temperature that alternates 4 times from −10° C. to40° C. every 48 hours.

According to still further features in the described preferredembodiments the carrier is selected such that the formulation is stableupon cycling at a temperature that alternates at least 3 times fromabout −10° C. to about 40° C. about every 48 hours.

According to still further features in the described preferredembodiments the carrier is selected such that the formulation is stableupon centrifugation at about 3,000 RPM for 10 minutes and then at 10,000RPM for an additional 10 minutes.

Another aspect of the present invention provides a chemically andphysically stable formulation for topical application comprising atellurium-containing compound, having at least one tellurium dioxomoiety, in a concentration of at least 5 weight percents of the totalweight of the formulation and a pharmaceutically acceptable carrier.

According to further features in the preferred embodiments of theinvention described below, in any one of the formulations describedherein the carrier comprises a glycol or an alcohol.

According to further features in the preferred embodiments of theinvention described below, in any one of the formulations describedherein the carrier comprises at least one C1-4 alkylene glycol.

According to still further features in the described preferredembodiments the at least one alkylene glycol comprises a polyethyleneglycol.

According to still further features in the described preferredembodiments the polyethylene glycol has an average molecular weight thatranges from about 100 Da to about 10000 Da.

According to still further features in the described preferredembodiments the carrier comprises a mixture of polyethylene glycolsselected so as to provide the formulation with a desired consistency(e.g., viscosity) applicable for topical formulation and/or to provide aformulation that is conveniently applied and/or absorbed.

According to still further features in the described preferredembodiments the carrier further comprises at least one ingredientselected from the group consisting of a stabilizer, a penetrationenhancer, a humectant, a deodorant, an aroma modifier, anantiperspirant, a sun screening agent, a sunless tanning agent, a hairconditioning agent, a pH adjusting agent, a sun blocking agent, achelating agent, a preservative, an emulsifier, an occlusive agent, anemollient, a thickener, a solubilizing agent, an anti-irritant, acolorant, a propellant and a surfactant.

According to still further features in the described preferredembodiments the additional ingredient is selected from the groupconsisting of propylene glycol and DMSO.

According to still further features in the described preferredembodiments the carrier further comprises at least one penetrationenhancer.

According to still further features in the described preferredembodiments a concentration of the penetration enhancer ranges fromabout 1 weight percent to about 10 weight percents.

According to still further features in the described preferredembodiments the at least one penetration enhancer is selected from thegroup consisting of propylene glycol (PG), dimethylsulfoxide (DMSO),dimethyl formamide (DMF), allantoin, urazole, N,N-dimethylacetamide(DMA), decylmethylsulfoxide (C₁₀ MSO), polyethylene glycol monolaurate(PEGML), propylene glycol monolaurate (PGML), PHOSAL®, glycerolmonolaurate (GML), lecithin, 1-substituted azacycloheptan-2-ones,alcohols, vegetable oil, phosphatidylcholine concentrate (PC), andmixtures thereof.

According to still further features in the described preferredembodiments the carrier further comprises at least one surfactant.

According to still further features in the described preferredembodiments a concentration of the at least one surfactant ranges fromabout 1 weight percent to about 10 weight percents.

According to still further features in the described preferredembodiments the at least one surfactant is selected from the groupconsisting of non-ionic surfactant, anionic surfactant, cationicsurfactant and amphiphilic surfactant.

According to still further features in the described preferredembodiments the surfactant is selected from the group consisting ofTweens (polyoxyethylene sorbitan monolaurate), tritons (octoxynol),tyloxapol, pluronics, Brijes (nonionic polyoxyethylene surfactants),Spans (sorbitan mono-octadecenoate), poloxamers and emulphors.

According to still further features in the described preferredembodiments any of the formulations described herein further comprisingan additional active agent.

According to still further features in the described preferredembodiments the additional active agent is selected from the groupconsisting of an antibiotic agent, an antimicrobial agent, an anti-acneagent, an antibacterial agent, an antifungal agent, an antiviral agent,a steroidal anti-inflammatory agent, a non-steroidal anti-inflammatoryagent, an anesthetic agent, an antipruriginous agent, an antiprotozoalagent, an anti-oxidant, a chemotherapeutic agent, an antidepressant, ananti histamine, a vitamin, a hormone, a keratolytic agent and anantidandruff agent.

According to still further features in the described preferredembodiments a concentration of the tellurium-containing compound rangesfrom about 0.01 weight percent to about 50 weight percents.

According to still further features in the described preferredembodiments a concentration of the tellurium containing compound rangesfrom about 1 weight percent to about 20 weight percents.

According to still further features in the described preferredembodiments a concentration of the tellurium-containing compound rangesfrom about 10 weight percents to about 20 weight percents.

According to still further features in the described preferredembodiments the tellurium-containing compound is selected from the groupconsisting of tellurium dioxide (TeO₂), a complex of TeO₂, a compoundhaving general Formula I:

a compound having general Formula II:

a compound having general Formula III:

and

a compound having general Formula IV:

wherein:

each of t, u and v is independently 0 or 1;

each of m and n is independently an integer from 0 to 3;

each of j and k is independently an integer from 0 to 4;

Y is selected from the group consisting of ammonium, phosphonium,potassium, sodium and lithium;

X is a halogen atom; and

each of R₁-R₂₂ is independently selected from the group consisting ofhydrogen, hydroxyalkyl, hydroxy, thiohydroxy, alkyl, alkenyl, alkynyl,alkoxy, thioalkoxy, halogen, haloalkyl, carboxy, carbonyl,alkylcarbonylalkyl, carboxyalkyl, acyl, amido, cyano,N-monoalkylamidoalkyl, N,N-dialkylaxnidoalkyl, cyanoalkyl, alkoxyalkyl,carbamyl, cycloalkyl, heteroalicyclic, sulfonyl, sulfinyl, sulfate,amine, aryl, heteroaryl, phosphate, phosphonate and sulfonamido.

According to still further features in the described preferredembodiments the tellurium-containing compound has general Formula I.

According to still further features in the described preferredembodiments t, u and v are each 0.

According to still further features in the described preferredembodiments R₁, R₈, R₉ and R₁₀ are each hydrogen.

According to still further features in the described preferredembodiments X is chloro.

According to still further features in the described preferredembodiments Y is ammonium.

According to still further features in the described preferredembodiments the formulation described herein is a hydrophilicformulation.

According to still further features in the described preferredembodiments the formulation described herein is a washable formulation.

According to still further features in the described preferredembodiments the formulation described herein has a viscosity in therange of from about 1,000 cpi to about 1,000,000 cpi at roomtemperature.

According to still further features in the described preferredembodiments the formulation described herein has a viscosity in therange of from about 3,000 cpi to about 30,000 cpi at room temperature.

According to still further features in the described preferredembodiments the formulation described herein is packaged in a packagingmaterial and identified in print, in or on the packaging material, foruse in the treatment of medical condition in which topical applicationof the tellurium-containing compound is beneficial.

According to still further features in the described preferredembodiments the formulation described herein is a the medical conditionis selected from the group consisting of scleroderma, psoriasis, atopicdermatitis, scarring, a human papilloma virus related skin and/ormucosal membrane ailment, condilloma, warts, alopecia, hair loss,metastatic melanoma, basal cell carcinoma, actinic keratosis and UV skindamage.

According to still further features in the described preferredembodiments the formulation described herein is in a form selected fromthe group consisting of a cream, an ointment, a paste, a gel, a lotion,a milk, a suspension, a solution, an aerosol, a spray, a foam, ashampoo, a mousse, a serum, a swab, a pledget, a pad, a tincture, apatch and a soap.

According to an additional aspect of the present invention there isprovided a method of treating or preventing a condition in which topicalapplication of a tellurium-containing compound is beneficial, the methodcomprising administering to a subject in need thereof a therapeuticallyeffective amount of a formulation as described herein.

According to a further aspect of the present invention there is provideda process of preparing the formulations described herein, the processcomprising mixing the tellurium-containing compound and the carrier.

According to further features in preferred embodiments of the inventiondescribed below, the mixing is conducted at a temperature that rangesfrom about 10° C. to about 100° C.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although methods and materialssimilar or equivalent to those described herein can be used in thepractice or testing of the present invention, suitable methods andmaterials are described below. In case of conflict, the patentspecification, including definitions, will control. In addition, thematerials, methods, and examples are illustrative only and not intendedto be limiting.

As used herein the term “method” refers to manners, means, techniquesand procedures for accomplishing a given task including, but not limitedto, those manners, means, techniques and procedures either known to, orreadily developed from known manners, means, techniques and proceduresby practitioners of the chemical, pharmacological, biological,biochemical and medical arts.

As used herein, the term “treating” includes abrogating, substantiallyinhibiting, slowing or reversing the progression of a condition,substantially ameliorating clinical or aesthetical symptoms of acondition or substantially preventing the appearance of clinical oraesthetical symptoms of a condition.

The term “comprising” means that other steps and ingredients that do notaffect the final result can be added. This term encompasses the terms“consisting of” and “consisting essentially of.”

The phrase “consisting essentially of” means that the composition ormethod may include additional ingredients and/or steps, but only if theadditional ingredients and/or steps do not materially alter the basicand novel characteristics of the claimed composition or method.

As used herein, the term “pharmaceutically acceptable” means approved bya regulatory agency of the Federal or a state government or listed inthe U.S. Pharmacopeia or other generally recognized pharmacopeia for usein animals, and more particularly in humans. Herein, the phrases“physiologically suitable carrier” and “pharmaceutically acceptablecarrier” are interchangeably used and refer to an approved carrier or adiluent that does not cause significant irritation to an organism anddoes not abrogate the biological activity and properties of theadministered conjugate.

As used herein, the singular form “a,” “an,” and “the” include pluralreferences unless the context clearly dictates otherwise. For example,the term “a compound” or “at least one compound” may include a pluralityof compounds, including mixtures thereof.

Throughout this disclosure, various aspects of this invention can bepresented in a range format. It should be understood that thedescription in range format is merely for convenience and brevity andshould not be construed as an inflexible limitation on the scope of theinvention. Accordingly, the description of a range should be consideredto have specifically disclosed all the possible subranges as well asindividual numerical values within that range. For example, descriptionof a range such as from 1 to 6 should be considered to have specificallydisclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numberswithin that range, for example, 1, 2, 3, 4, 5, and 6. This appliesregardless of the breadth of the range.

Whenever a numerical range is indicated herein, it is meant to includeany cited numeral (fractional or integral) within the indicated range.The phrases “ranging/ranges between” a first indicate number and asecond indicate number and “ranging/ranges from” a first indicate number“to” a second indicate number are used herein interchangeably and aremeant to include the first and second indicated numbers and all thefractional and integral numerals therebetween.

As used herein the term “about” means+/−10%.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although methods and materialssimilar or equivalent to those described herein can be used in thepractice or testing of the present invention, suitable methods andmaterials are described below. In case of conflict, the patentspecification, including definitions, will control. In addition, thematerials, methods, and examples are illustrative only and not intendedto be limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, withreference to the accompanying drawings. With specific reference now tothe drawings in detail, it is stressed that the particulars shown are byway of example and for purposes of illustrative discussion of thepreferred embodiments of the present invention only, and are presentedin the cause of providing what is believed to be the most useful andreadily understood description of the principles and conceptual aspectsof the invention. In this regard, no attempt is made to show structuraldetails of the invention in more detail than is necessary for afundamental understanding of the invention, the description taken withthe drawings making apparent to those skilled in the art how the severalforms of the invention may be embodied in practice.

In the drawings:

FIGS. 1A and 1B present photos of AS101 powder (FIG. 1A) and a 20% (byweight) solution of AS101 in DMSO (FIG. 1B), after storage for 30 daysat ambient temperature in scintillation glass bottles having aluminumlaminated non-sealed caps;

FIGS. 2A-2D present photos of AS101 powder (FIG. 2A), a 20% (by weight)solution of AS101 in DMSO (FIG. 2B) and AS101 ointment in DMSO/Petroleumjelly (FIGS. 2C and 2D) under polarized light; and

FIGS. 3A and 3B present images of the tellurium-containing PGB3formulation, according to preferred embodiments of the presentinvention, under polarized light at ×100 magnification (FIG. 3A) and at×400 magnification (FIG. 3B).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention is of novel formulations of tellurium containingcompounds. More specifically, the present invention is oftellurium-containing formulations that are designed for topicalapplication. The novel formulations of tellurium-containing compounds ofthe present invention are characterized by chemical and physicalstability when the tellurium-containing compound is present therein inlow as well as in high and very high concentrations.

The principles and operation of the compositions and methods accordingto the present invention may be better understood with reference to theaccompanying descriptions.

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not limited in its applicationto the details set forth in the following description or exemplified bythe Examples. The invention is capable of other embodiments or of beingpracticed or carried out in various ways. Also, it is to be understoodthat the phraseology and terminology employed herein is for the purposeof description and should not be regarded as limiting.

As mentioned in the Background section hereinabove, tellurium-containingcompounds, for example, ammonium trichloro(dioxyethylene-O,O′) tellurate(also known in the art as AS101) and [TeO₄(COCH)₂]₂ (also known in theart as SAS), have proven therapeutic properties. In one particular,topical application of tellurium-containing compounds and pharmaceuticalcompositions thereof, has been found effective in the treatment ofvarious skin-related conditions, diseases and disorders, such as skinand mucosal membrane ailments caused by human papilloma viruses (HPV),in the treatment or prevention of alopecia and other conditionsassociated with hair loss, and in the treatment of basal cell carcinoma(BCC), actinic keratosis (AK), damages caused by exposure to UVirradiation, atopic dermatitis, Kaposi's sarcoma, scleroderma, burns,scarring and metastatic melanoma (see, for example, WO 2005/069735, U.S.Provisional Patent Application Nos. 60/610,660, 60/716,923 and60/716,924, U.S. Pat. Nos. 6,552,089, 5,262,149 and 6,472,381, Sun etal. 1996, supra).

As is further discussed in the Background section hereinabove,tellurium-containing compounds, especially tellurium-containingcompounds which are derived from tellurium dioxide and hence have atleast one tellurium dioxo moiety, are known to exhibit an oxidativepotential and, under certain conditions, may be considered unstable,both physically and chemically. Thus, when formulated intopharmaceutical compositions, particularly for topical application, inwhich their concentration is often relatively high, compounds containingtellurium dioxo moieties may be involved in oxidation and otherreactions, which may lead, for example, to coloration of thepharmaceutical composition, and/or degradation of various componentstherein. As detailed in the Background section, when such telluriumdioxo-containing compounds are packaged, or come in other contact, withmetallic substances, such as aluminum, the metals are rapidly oxidizedby the tellurium-containing compounds.

The oxidative nature of tellurium-containing compounds isre-demonstrated in the Examples section below, wherein exemplary samplesof AS101 (as a powder, as a 20% by weight solution in DMSO, and as anointment containing the DMSO solution in combination with petroleumjelly) were visually tested. As can be seen in FIGS. 1A-B, the aluminumlaminate cap of the bottles in which both the AS101 powder (FIG. 1A) andthe 20% AS101 solution in DMSO (FIG. 1B) were stored, practicallydecomposed. Furthermore, a dark, black color was produced upon anycontact of the tellurium-containing compound (AS101) with metalequipment, again confirming the oxidative nature thereof. The DMSOsolution formulation and the ointment formulation further appeared todecompose upon storage.

Herein throughout, the phrases “tellurium dioxo moiety” and “telluriumdioxide moiety” are used interchangeably, and describe an —O—Te—O—group, in which the tellurium center can be further substituted.

Thus, presently available topical formulations comprisingtellurium-containing compounds suffer from moderate stability,necessitating the use of special sealed containers during handling,packaging, storage and practice thereof. These special requirementsinvariably increase the cost of production of the pharmaceuticalproducts based on tellurium-containing compounds, and lower thepracticality of their use.

As is further discussed in the Background section hereinabove,tellurium-containing compounds have a very low solubility in aqueouscarriers, and thus most currently-available formulations are based onhydrophobic carriers (for example petrolatum, such as petroleum jellycream) which, by often being greasy and staining, are less desirable. Asdemonstrated in the Examples section below, an exemplarytellurium-containing compound (AS101) was, on one hand, solubilized(FIG. 2B) yet moderately stable (FIG. 1B) in DMSO, and on the otherhand, was not solubilized in the DMSO/petroleum jelly ointment,re-crystallizing into another polymorphic type (FIGS. 2C and 2D).

Novel, stable aqueous formulations comprising tellurium-containingcompounds, which would be suitable for topical application are thereforehighly desirable.

In a search of such novel formulations, it was surprisingly found thattellurium-containing compounds can be formulated into stable aqueoustopical formulations, which are devoid of the disadvantages associatedwith the presently known tellurium-containing topical formulationsdescribed hereinabove.

As shown in the Examples section below, an exemplary topical formulationcontaining 12% of the tellurium-containing compound AS101 has beendeveloped as a prototype formulation of substantially solubilizedtellurium-containing compound. The formulation further comprisedpharmaceutical inactive ingredients which are approved for topicalprescription drugs by the FDA and the European authorities. The obtainedproduct was a semi-solid hydrophilic ointment, characterized by a goodskin feeling, ease of application, and a non-greasy, non-sticky nature.This formulation successfully passed a set of accelerated instabilityphysical tests and further showed good chemical stability. Anotherexemplary topical formulation, containing 15% of thetellurium-containing compound AS101 has been developed and was alsofound to remain stable upon storage. Other exemplary formulationscontaining 12% of the tellurium-containing compound AS101 are alsopresented.

The present invention therefore successfully addresses the shortcomingsof the presently known configurations by providing chemically andphysically stable formulations of therapeutically activetellurium-containing compounds, suitable for topical application,allowing the formulation of stable tellurium-containing compounds in anydesired concentration.

Thus, according to one aspect of the invention, there is provided aformulation for topical application which comprises atellurium-containing compound, preferably a compound derived fromtellurium dioxide which has one or more tellurium dioxo moieties. Theformulation, according to this aspect of the present invention, furthercomprises a pharmaceutically acceptable carrier which is selected suchthat when the tellurium-containing compound is present therein in aconcentration of 10 weight percents, it is soluble, dispersible and/orsuspendable therein; and the formulation is chemically and physicallystable upon storage at room temperature for at least 30 days.

Hereinafter, the phrase “pharmaceutically acceptable carrier” refers toa carrier or a diluent that does not cause significant irritation to thesubject and does not abrogate the biological activity and properties ofthe administered compound. As used herein, the term “carrier” refers toa diluent, adjuvant, excipient, or vehicle with which the therapeutic isadministered.

Herein the term “excipient” refers to an inert substance added to apharmaceutical composition to further facilitate administration of anactive ingredient. Examples, without limitation, of excipients includecalcium carbonate, calcium phosphate, various sugars and types ofstarch, cellulose derivatives, gelatin, vegetable oils and polyethyleneglycols.

Hereinafter, the phrase “topical application” refers to directapplication to an external surface or to a cavity of tissues of thebody.

Topical application of the tellurium-containing compounds describedherein is preferably effected by applying a therapeutically effectiveamount of a tellurium-containing compound onto a treated skin or mucosalarea.

The treated area can be, for example, an area of the face, ears, neck,scalp, shoulder, back, forearm, hand, chest leg or vagina.

Herein, the phrase “treated area” encompasses the affected area as wellas the tissues surrounding the affected area. The topical application iseffected over and around the clinical manifestation.

The term “therapeutically effective amount” or “pharmaceuticallyeffective amount” denotes that dose of an active ingredient or acomposition comprising the active ingredient that will provide thetherapeutic effect for which the active ingredient is indicated.Pharmaceutical compositions suitable for use in context of the presentinvention include compositions wherein the active ingredients arecontained in an amount effective to achieve the intended purpose. Morespecifically, a therapeutically effective amount means an amount ofactive ingredients effective to prevent, alleviate or amelioratesymptoms of disease or prolong the survival of the subject beingtreated. Determination of a therapeutically effective amount is wellwithin the capability of those skilled in the art.

The therapeutically effective amount or dose can be estimated initiallyfrom in vitro assays, e.g., performed on human or animal skin. Forexample, a dose can be formulated in animal models and such informationcan be used to more accurately determine useful doses in humans.

Toxicity and therapeutic efficacy of the active ingredients describedherein can be determined by standard pharmaceutical procedures in vitro,in cell cultures experimental animals or humans. The data obtained fromthese in vitro and cell culture assays and animal or human studies canbe used in formulating a range of dosage for use in human. The dosagemay vary depending upon the dosage form employed and the route ofadministration utilized. The exact formulation, route of administrationand dosage can be chosen by the individual physician in view of thepatient's condition. [See e.g., Fingl, et al., (1975) “ThePharmacological Basis of Therapeutics”, Ch. 1 p. 1].

Depending on the severity and responsiveness of the condition to betreated, dosing can be of a single or a plurality of administrations,with course of treatment lasting from several days to several weeks oruntil cure is effected or diminution of the disease state is achieved.

As demonstrated in the Examples section below, by selecting a suitablecarrier, the tellurium-containing formulation can be obtained as achemically and physically stable formulation, such that an exemplaryformulation comprising 10 weight percents of the active telluriumcontaining compound (formulation PGB3) is soluble, dispersible and/orsuspendable therein; and at the same time is chemically and physicallystable upon storage at room temperature for at least 30 days, at least60 days, at least 90 days, and even for 6 months, and is even stableupon storage at 40° C. for at least 30 days, and even as much as 90 daysand more. In certain embodiments, formulations of the invention areprovided as kits, which may include for example instructions for use andadministration.

The phrase “chemically stable” refers to the absence of any chemicalchange in the tellurium-containing compound upon storage in dissolved orsolid state. Examples of processes involving chemical change include,but are not limited to, hydrolysis, oxidation, etc. In particular, inview of the known findings that the tellurium-containing compoundsexhibit an oxidative potential, processes involving chemical change mayinclude redox reactions. Thus, in a “chemically stable” formulation, thevarious chemical components, especially the tellurium-containingcompound, do not exhibit noticeable chemical change.

The phrase “physically stable” relates to the formation of insolubleand/or soluble aggregates as well as any structural deformation,discoloration and/or darkening of any of the formulation's ingredients.This phrase is further used herein with reference to maintenance ofviscosity, resistance to syneresis, and in the case of emulsions,resistance to phase separation. Thus, a “physically stable” formulation,does not exhibit a noticeable change of its physical propertiesincluding solubility, color, viscosity, phase separation and the like.

Although the terms “chemically stable” and “physically stable” have beenseparately defined herein, they are not necessarily distinct, and mayinfluence each other.

As demonstrated in the Examples section below, exemplary formulationsaccording to the present embodiments were subjected to a thermalstability test, comprised of four daily temperature cycles of between−10° C. and 40° C., and lasting 48 hours. In another experiment, eachsample was further placed in a 40° C. stability chamber for 90 days foran accelerated test.

Thus, the stability of the formulation may be defined based on itsthermal stability, whereas according to a preferred embodiment of thepresent invention, the carrier is selected such that the formulation isstable upon cycling (mixing) at a temperature that alternates from about−10° C. to about 40° C. every 48 hours.

According to another preferred embodiment of the present invention, thecarrier is selected such that the formulation is stable upon mixing(centrifugation) at about 3,000 RPM for about 10 minutes and then atabout 10,000 RPM for about 10 minutes.

As demonstrated in the Examples section which follows, topicalformulations containing 12% or 15% AS101 were prepared as semi-solidhydrophilic ointments (referred to herein as formulations PGB3 and PGB5,respectively), which are well suited for topical applications. Thepresently-developed formulations have good skin feeling, are easy toapply and do not have greasy or sticky characteristics. Theseformulations have successfully passed a set of accelerated instabilityphysical tests. The chemical stability of AS101 was assessed by the lackof color change during the accelerated stability tests, since AS101powder, or AS101 solution are known to become gray or black upon anyminor oxidation (see, for example, Example 1).

Certain embodiments comprise about 12% AS101, about 13% AS101, about 14%AS101, and about 15% AS101. In other embodiments, topical formulationscomprising AS101 in amounts of less than about 12% and greater thanabout 15% are used, including without limitation about 10%, about 11%,about 10% to about 12%, about 5% to about 10%, about 16%, about 17%,about 18%, about 19%, about 20%, about 12% to about 15%, about 15% toabout 20%, about 20% to about 25%, about 25% to about 30%, about 30% toabout 35%, and about 35% to about 40% AS101.

Solubilized or molecular forms of an active pharmaceutical ingredientare generally associated with better skin absorption in comparison toformulations in which the active ingredient is present in a crystallineform. In order to develop formulations comprising solubilized forms oftellurium-containing compounds, the solubility of these compounds wasevaluated for a large variety of commonly used solvents.

As demonstrated in the Examples section that follows, although manypharmaceutically acceptable carriers have been tested in the course ofexperimentation, some were found incompatible. For example, as presentedin Table 1 below, in the presence of solvents such as silicone oil andhydroxycellulose, which are generally accepted in cosmetic applications,undesirable coloration of the solution was observed, suggesting that theuse these solvents as carriers for tellurium-containing compositions islimited.

Thus, any one or more carriers may be used in the preparation of theformulations of the present invention, provided they provide thechemical and physical stabilities described herein. This is readilydetenninable following the chemical and physical stability testsdescribed herein and exemplified in the examples section that follows.

As detailed in the Background section above, topicaltellurium-containing formulations comprising C1-4 alkylene glycolcarriers, such as polyethylene glycol (PEG), were mentioned only inpassing, and no such stable formulations have been demonstrated. The useof C1-4 alkylene glycols, such as PEGs, as carriers in the preparationof stable topical formulations of tellurium-containing compounds has nowbeen unexpectedly demonstrated. Thus, according to an exemplaryembodiment of the present invention, the carrier comprises at least oneC1-4 alkylene glycol. Preferably, the at least one alkylene glycolcomprises a polyethylene glycol.

Polyethylene glycols are polymers of ethylene oxide having the generalformula: HO—CH₂—O—(CH₂—O—CH₂)n-OCH₂OH where n represents the number ofoxyethylene groups and can be any integer from 1 to 100,000. The PEGsare designated by a numerical value, which is indicative of the averagemolecular weight for a given grade. PEGs having a molecular weight lowerthan 600 are liquids, and PEGs having molecular weights of above 1000are solids at room temperature. PEGs are generally regarded as non-toxicand non-irritating.

According to a preferred embodiment of the present invention, thepolyethylene glycol has an average molecular weight that ranges fromabout 100 to about 10,000.

As can be seen in the Examples section that follows, PEGs being withinsuch a range of molecular weight were confirmed to be suitable as acarrier in topical formulations comprising tellurium-containingcompounds.

As can be further seen in the Examples section that follows, in thepreparation of topical formulations of the present invention, PEG 200,PEG 400 and PEG 4000 were used, and a combination thereof achieved astable tellurium-containing formulation (see, Example 3).

Thus, according to an exemplary embodiment of the present invention, thepolyethylene glycol is selected from the group consisting of PEG 200,PEG 400, PEG 4000 and any combination thereof.

According to another preferred embodiment of the present invention, thecarrier comprises additional suitable carriers.

Since PEG molecular weights of below 600 are liquids, and since it ispreferable that the tellurium-containing compound be at least partiallyliquidated, the formulation comprises at least one polyethylene glycolhaving an average molecular weight lower than 600. The concentration ofthe liquid PEGs (i.e., those having an average molecular weight lowerthan 600) preferably ranges from about 30 weight percents to about 90weight percents of the total weight of the composition.

As can be seen in the Examples section that follows, a preferredformulation, according to the present invention, comprises about 39weight percents PEG 200 and about 30 weight percents PEG 400. Theseformulations exemplify other embodiments comprising about 35 to 40weight percent PEG 200 (e.g. 36%, 37%, 38%, 39%, and 40%), or about 30to 50 weight percent PEG 200, and about 25 to 35 weight percent PEG 400(e.g. 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, and 35%). Incertain preferred embodiments, the concentration of either PEG 200, orPEG 400, each ranges from about 10 weight percents to about 50 weightpercents of the total weight of the composition.

However, while in topical formulations, it is often desirable toincrease the viscosity of the formulation, and given that PEG molecularweights of above 1000 are solids at room temperature, at least onepolyethylene glycol having an average molecular weight higher than 1000,can be advantageously added to the formulation. The concentration of asolid PEG (i.e., one having an average molecular weight higher than1000) preferably ranges from about 5 weight percents to about 20 weightpercents.

As can be seen in the Examples section below, a preferred formulation,according to the present invention, comprises about 10 weight percentsof PEG 4000.

Thus, the preferred concentration of PEG 4000 ranges from about 5 weightpercents to about 20 weight percents.

However, it should be evident to any person skilled in the art thatother liquid and/or solid PEGS, such as, for example, PEG 150, PEG 200,PEG 600, PEG 1500, PEG 3500 and PEG 6000, as well as any combinationthereof, are suitable for use in the context of the present embodiments,while selecting/composing the desired consistency of the formulation.

Thus, various. PEGs, having various molecular weights, can be selectedso as achieve the desired consistency of the formulation (e.g., in termsof viscosity, as is detailed hereinbelow), the desired convenience totopically apply the formulation, and the desired absorbance of thecomposition, as is further discussed in detail hereinbelow.

All of these concentrations given hereinabove comply with the inactiveingredients guideline limits as published by the FDA and by the Europeanauthorities.

The formulations described herein can optionally further comprise avariety of components that are suitable for providing the compositionswith additional usage benefits. Such conventional optional componentsare well known to those skilled in the art and are referred to herein as“ingredients”. Some non-limiting representative examples of theseingredients include penetration enhancers, stabilizers, humectants,deodorants, aroma modifiers, antiperspirants, sun screening agents,sunless tanning agents, hair conditioning agents, pH adjusting agents,chelating agents, preservatives, emulsifiers, occlusive agents,emollients, thickeners, solubilizing agents, anti-irritants, colorants,propellants and surfactants.

It should be noted, however, that the additional ingredients areselected suitable (compatible) for being formulation in combination withthe tellurium-containing compound.

In the course of the studies described herein, it has been found thatupon addition of certain ingredients, a formulation having enhancedstability was obtained. Thus, for example, it has been found that uponadding propylene glycol to the tellurium-containing compound, nodecomposition, coloration or any other adverse feature was observedduring the formulation process and the following storage. Additionally,it was found that the presence of relatively low amounts of DMSO (about5%) in the formulation, rendered it highly stable. Both propylene glycoland DMSO are recognized herein as highly effective penetration enhancersand hence their inclusion as additives in the formulation is highlybeneficial.

Other substances that can act as stabilizing agents of thetellurium-containing compounds and/or of residual (ppm) amounts ofimpurities thereof can be included in the formulations described herein.Alternatively, stabilizers, which affect the formulation stability interms of its uniformity, smoothness and consistency, are preferablyincluded within the formulation described herein. Such stabilizers canbe, for example, non-ionic, anionic, cationic and/or amphiphilicsurfactants. Preferably, the stabilizer is a non-ionic surfactant suchas, but not limited to, polyethoxylated fatty alcohols and glycerolderivatives. Representative examples of surfactants include, withoutlimitation, Tweens, tritons, tyloxapol, pluronics, Brijes, Spans,poloxamers and emulphors. A particularly presently preferred exemplarysurfactant is a polyethoxylated fatty alcohol marketed under thetrademark “BRIJ” by ICI Americas, Inc.

Alternatively, the stabilizer is an anionic surfactant such as, but notlimited to, alkyl and aryl sulphonate or phosphate. Also alternatively,the stabilizer is a cationic surfactant such as cetyl pyridiniumchloride or bromide, and cetyl trimethylammonium bromide. Alternativelyand preferably, the stabilizer is an amphiphilic surfactant such as, butnot limited to, alkyl betaine derivatives, cocoamphodiacetalederivatives, lauroamphoacetates and phosphatidylglycerol.

In addition, as mentioned hereinabove, the formulations described hereincan comprise penetration enhancers. As is well known in the art, apenetration enhancer is a compound capable of enhancing the transdermalpenetration of an active ingredient through the skin layer. Suitablepenetration enhancers which are usable in context of the presentinvention include, but are not limited to, dimethylsulfoxide (DMSO),dimethyl formamide (DMF), allantoin, urazole, N,N-dimethylacetamide(DMA), decylmethylsulfoxide (C₁₀ MSO), polyethylene glycol monolaurate(PEGML), propylene glycol (PG), propylene glycol monolaurate (PGML),PHOSAL®, glycerol monolaurate (GML), lecithin, the 1-substitutedazacycloheptan-2-ones, particularly 1-n-dodecylcyclazacycloheptan-2-one,alcohols, and the like. The penetration enhancer may also be a vegetableoil. Such oils include, for example, safflower oil, cottonseed oil andcorn oil. Preferable penetration enhancers, as exemplified below, arepropylene glycol and PHOSAL 50PG™.

Representative examples of humectants that are usable in this context ofthe present invention include, without limitation, guanidine, glycolicacid and glycolate salts (e.g. ammonium slat and quaternary alkylammonium salt), aloe vera in any of its variety of forms (e.g., aloevera gel), allantoin, urazole, polyhydroxy alcohols such as sorbitol,glycerol, hexanetriol, propylene glycol, butylene glycol, hexyleneglycol and the like, sugars and starches, sugar and starch derivatives(e.g., alkoxylated glucose), hyaluronic acid, lactamidemonoethanolamine, acetamide monoethanolamrine and any combinationthereof.

The compositions of the present invention can further comprise a pHadjusting agent. The addition of a pH-adjusting agent is particularlypreferred when the compositions are applied topically on the skin. ThepH of these treated areas is typically lower than 6.0. Hence, it ispreferable for the compositions of the present invention to have a pHvalue of between about 4 and about 7, preferably between about 4 andabout 6, so as to avoid irritations to the skin or induction ofimbalance of the bacteria population of the genital areas. Suitable pHadjusting agents include, for example, one or more of adipic acids,glycines, citric acids, calcium hydroxides, magnesiumaluminometasilicates, buffers or any combinations thereof.

Representative examples of deodorant agents that are usable in thecontext of the present invention include, without limitation, quaternaryammonium compounds such as cetyl-trimethylammonium bromide, cetylpyridinium chloride, benzethonium chloride, diisobutyl phenoxy ethoxyethyl dimethyl benzyl ammonium chloride, sodium N-lauryl sarcosine,sodium N-palmlthyl sarcosine, lauroyl sarcosine, N-myristoyl glycine,potassium N-lauryl sarcosine, stearyl, trimethyl ammonium chloride,sodium aluminum chlorohydroxy lactate, tricetylmethyl ammonium chloride,2,4,4′-trichloro-2′-hydroxy diphenyl ether, diaminoalkyl amides such asL-lysine hexadecyl amide, heavy metal salts of citrate, salicylate, andpiroctose, especially zinc salts, and acids thereof, heavy metal saltsof pyrithione, especially zinc pyrithione and zinc phenolsulfate. Otherdeodorant agents include, without limitation, odor absorbing materialssuch as carbonate and bicarbonate salts, e.g. as the alkali metalcarbonates and bicarbonates, ammonium and tetraalkylammonium carbonatesand bicarbonates, especially the sodium and potassium salts, or anycombination of the above.

Antiperspirant agents can be incorporated in the compositions of thepresent invention either in a solubilized or a particulate form andinclude, for example, aluminum or zirconium astringent salts orcomplexes.

Representative examples of sun screening agents usable in context of thepresent invention include, without limitation, p-aminobenzoic acid,salts and derivatives thereof (ethyl, isobutyl, glyceryl esters;p-dimethylaminobenzoic acid); anthranilates (i.e., o-amino-benzoates;methyl, menthyl, phenyl, benzyl, phenylethyl, linalyl, terpinyl, andcyclohexenyl esters); salicylates (amyl, phenyl, octyl, benzyl, menthyl,glyceryl, and di-pro-pyleneglycol esters); cinnamic acid derivatives(menthyl and benzyl esters, a-phenyl cinnamonitrile; butyl cinnamoylpyruvate); dihydroxycinnamic acid derivatives (umbelliferone,methylumbelliferone, methylaceto-umbelliferone); trihydroxy-cinnamicacid derivatives (esculetin, methylesculetin, daphnetin, and theglucosides, esculin and daphnin); hydrocarbons (diphenylbutadiene,stilbene); dibenzalacetone and benzalacetophenone; naphtholsulfonates(sodium salts of 2-naphthol-3,6-disulfonic and of2-naphthol-6,8-disulfonic acids); di-hydroxynaphthoic acid and itssalts; o- and p-hydroxybiphenyldisulfonates; coumarin derivatives(7-hydroxy, 7-methyl, 3-phenyl); diazoles (2-acetyl-3-bromoindazole,phenyl benzoxazole, methyl naphthoxazole, various aryl benzothiazoles);quinine salts (bisulfate, sulfate, chloride, oleate, and tannate);quinoline derivatives (8-hydroxyquinoline salts, 2-phenylquinoline);hydroxy- or methoxy-substituted benzophenones; uric and violuric acids;tannic acid and its derivatives (e.g., hexaethylether); (butyl carbotol)(6-propyl piperonyl) ether; hydroquinone; benzophenones (oxybenzene,sulisobenzone, dioxybenzone, benzoresorcinol,2,2′,4,4′-tetrahydroxybenzophenone,2,2′-dihydroxy-4,4′-dimethoxybenzophenone, octabenzone;4-isopropyldibenzoylmethane; butylmethoxydibenzoylmethane; etocrylene;octocrylene; [3-(4′-methylbenzylidene boman-2-one) and4-isopropyl-di-benzoylmethane, and any combination thereof.

Representative examples of sunless tanning agents usable in context ofthe present invention include, without limitation, dihydroxyacetone,glyceraldehyde, indoles and their derivatives. The sunless tanningagents can be used in combination with the sunscreen agents.

The chelating agents are optionally added to the compositions of thepresent invention so as to enhance the preservative or preservativesystem. Preferred chelating agents are mild agents, such as, forexample, ethylenediaminetetraacetic acid (EDTA), EDTA derivatives, orany combination thereof.

Suitable preservatives that can be used in the context of the presentcomposition include, without limitation, one or more alkanols, disodiumEDTA (ethylenediamine tetraacetate), EDTA salts, EDTA fatty acidconjugates, isothiazolinone, parabens such as methylparaben andpropylparaben, propylene glycols, sorbates, urea derivatives such asdiazolindinyl urea, or any combinations thereof.

Suitable emulsifiers that can be used in the context of the presentinvention include, for example, one or more sorbitans, alkoxylated fattyalcohols, alkylpolyglycosides, soaps, alkyl sulfates, monoalkyl anddialkyl phosphates, alkyl sulphonates, acyl isothionates, or anycombinations thereof.

Suitable occlusive agents that can be used in the context of the presentinvention include, for example, petrolatum, mineral oil, beeswax,silicone oil, lanolin and oil-soluble lanolin derivatives, saturated andunsaturated fatty alcohols such as behenyl alcohol, hydrocarbons such assqualane, and various animal and vegetable oils such as almond oil,peanut oil, wheat germ oil, linseed oil, jojoba oil, oil of apricotpits, walnuts, palm nuts, pistachio nuts, sesame seeds, rapeseed, cadeoil, corn oil, peach pit oil, poppy seed oil, pine oil, castor oil,soybean oil, avocado oil, safflower oil, coconut oil, hazelnut oil,olive oil, grape seed oil and sunflower seed oil.

Suitable emollients, that can be used in the context of the presentinvention include, for example, dodecane, squalane, cholesterol,isohexadecane, isononyl isononanoate, PPG Ethers, petrolatum, lanolin,safflower oil, castor oil, coconut oil, cottonseed oil, palm kernel oil,palm oil, peanut oil, soybean oil, polyol carboxylic acid esters,derivatives thereof and mixtures thereof.

Suitable thickeners that can be used in the context of the presentinvention include, for example, non-ionic water-soluble polymers such ashydroxyethylcellulose (commercially available under the TrademarkNATROSOL® 250 or 350), cationic water-soluble polymers such as Polyquat37 (commercially available under the Trademark SYNTHALEN), fattyalcohols, fatty acids and their alkali salts and mixtures thereof.

Representative examples of solubilizing agents that are usable in thecontext of the present invention include, without limitation,complex-forming solubilizers such as citric acid,ethylenediamine-tetraacetate, sodium meta-phosphate, succinic acid,urea, cyclodextrin, polyvinylpyrrolidone,diethylammonium-ortho-benzoate, and micelle-forming solubilizers such asTWEENS and SPANS, e.g., TWEEN 80. Other solubilizers that are usable forthe compositions of the present invention are, for example,polyoxyethylene sorbitan fatty acid ester, polyoxyethylene n-alkylethers, n-alkyl amine n-oxides, poloxamers, organic solvents,phospholipids and cyclodextrines.

Suitable anti-irritants that can be used in the context of the presentinvention include, for example, steroidal and non steroidalanti-inflammatory agents or other materials such as aloe vera,chamomile, alpha-bisabolol, cola nitida extract, green tea extract, teatree oil, licorice extract, allantoin, caffeine or other xanthines,glycyrrhizic acid and its derivatives.

It is important to note that some inactive ingredients, such as siliconeoils and cellulose polymers, which are common additives in the cosmeticindustry, were found to react with the tellurium-containing compound,causing unaccepted change of color (see Example 2).

The formulations of the present invention may further include one ormore additive(s), such as, but not limited to, fillers, salts, sugarsand/or glycerin. These additives are typically added to the formulationto reinforce the mechanical strength thereof, to alter the diffusion orabsorbency properties of it and/or to improve the cost-efficiency of theproduct.

In addition to the tellurium-containing compounds described above, theformulations described herein can further comprise an additional activeagent to provide an additive beneficial effect in terms of the ailmentbeing treated, conditions associated with the ailment being treated orother parameters such as psychological effects and prophylactic effects.

Thus, according to an additional embodiment of the present invention,each of the formulations described herein may further comprise anadditional active agent, known to be used for treating medicalconditions treated by topical formulations of tellurium-containingcompounds, as described hereinbelow.

The additional active agent can be, for example, an antibiotic agent, anantimicrobial agent, an anti-acne agent, an antibacterial agent, anantifungal agent, an antiviral agent, a steroidal anti-inflammatoryagent, a non-steroidal anti-inflammatory agent, an anesthetic agent, anantipruriginous agent, an antiprotozoal agent, an anti-oxidant, achemotherapeutic agent, an antidepressant, an anti histamine, a vitamin,a hormone, a keratolytic agent and an antidandruff agent. The activeagent is selected suitable for being combined with thetellurium-containing compound in terms of its compatibility.

Suitable anti-acne agents for use in this context of the presentinvention include, without limitation, keratolytics such as salicylicacid, sulfur, glycolic, pyruvic acid, resorcinol, and N-acetylcysteineand retinoids such as retinoic acid and its derivatives (e.g., cis andtrans, esters).

Suitable antibiotics for use in this context of the present inventioninclude, without limitation, benzoyl peroxide, octopirox, erythromycin,zinc, tetracyclin, triclosan, azelaic acid and its derivatives, phenoxyethanol and phenoxy proponol, ethylacetate, clindamycin andmeclocycline; sebostats such as flavinoids; alpha and beta hydroxyacids; and bile salts such as scymnol sulfate and its derivatives,deoxycholate and cholate.

Representative examples of non-steroidal anti-inflammatory agents thatare usable in this context of the present invention include, withoutlimitation, oxicams, such as piroxicam, isoxicam, tenoxicam, sudoxicam,and CP-14,304; salicylates, such as aspirin, disalcid, benorylate,trilisate, safapryn, solprin, diflunisal, and fendosal; acetic acidderivatives, such as diclofenac, fenclofenac, indomethacin, sulindac,tolmetin, isoxepac, furofenac, tiopinac, zidometacin, acematacin,fentiazac, zomepirac, clindanac, oxepinac, felbinac, and ketorolac;fenamates, such as mefenamic, meclofenamic, flufenamic, niflumic, andtolfenamic acids; propionic acid derivatives, such as ibuprofen,naproxen, benoxaprofen, flurbiprofen, ketoprofen, fenoprofen, fenbufen,indopropfen, pirprofen, carprofen, oxaprozin, pranoprofen, miroprofen,tioxaprofen, suprofen, alminoprofen, and tiaprofenic; pyrazoles, such asphenylbutazone, oxyphenbutazone, feprazone, azapropazone, andtrimethazone. Mixtures of these non-steroidal anti-inflammatory agentsmay also be employed, as well as the dermatologically acceptable saltsand esters of these agents. For example, etofenamate, a flufenamic acidderivative, is particularly useful for topical application.

Representative examples of steroidal anti-inflammatory drugs include,without limitation, corticosteroids such as hydrocortisone,hydroxyltriamcinolone, alpha-methyl dexamethasone,dexamethasone-phosphate, beclomethasone dipropionates, clobetasolvalerate, desonide, desoxymethasone, desoxycorticosterone acetate,dexamethasone, dichlorisone, diflorasone diacetate, diflucortolonevalerate, fluadrenolone, fluclorolone acetonide, fludrocortisone,flumethasone pivalate, fluosinolone acetonide, fluocinonide, flucortinebutylesters, fluocortolone, fluprednidene (fluprednylidene)acetate,flurandrenolone, halcinonide, hydrocortisone acetate, hydrocortisonebutyrate, methylprednisolone, triamcinolone acetonide, cortisone,cortodoxone, flucetonide, fludrocortisone, difluorosone diacetate,fluradrenolone, fludrocortisone, diflurosone diacetate, fluradrenoloneacetonide, medrysone, amcinafel, amcinafide, betamethasone and thebalance of its esters, chloroprednisone, chlorprednisone acetate,clocortelone, clescinolone, dichlorisone, diflurprednate, flucloronide,flunisolide, fluoromethalone, fluperolone, fluprednisolone,hydrocortisone valerate, hydrocortisone cyclopentylpropionate,hydrocortamate, meprednisone, paramethasone, prednisolone, prednisone,beclomethasone dipropionate, triamcinolone, and mixtures thereof.

Suitable antipruritic agents include, without limitation,pharmaceutically acceptable salts of methdilazine and trimeprazine.

Non-limiting examples of anesthetic drugs that are suitable for use incontext of the present invention include pharmaceutically acceptablesalts of lidocaine, bupivacaine, chlorprocaine, dibucaine, etidocaine,mepivacaine, tetracaine, dyclonine, hexylcaine, procaine, cocaine,ketamine, pramoxine and phenol.

Suitable antimicrobial agents, including antibacterial, antifungal,antiprotozoal and antiviral agents, for use in context of the presentinvention include, without limitation, beta-lactam drugs, quinolonedrugs, ciprofloxacin, norfloxacin, tetracycline, erythromycin, amikacin,triclosan, doxycycline, capreomycin, chlorhexidine, chlortetracycline,oxytetracycline, clindamycin, ethambutol, metronidazole, pentamidine,gentamicin, kanamycin, lineomycin, methacycline, methenamine,minocycline, neomycin, netilmicin, streptomycin, tobramycin, andmiconazole. Also included are tetracycline hydrochloride, farnesol,erythromycin estolate, erytiromycin stearate (salt), amikacin sulfate,doxycycline hydrochloride, chlorhexidine gluconate, chlorhexidinehydrochloride, chlortetracycline hydrochloride, oxytetracyclinehydrochloride, clindamycin hydrochloride, ethambutol hydrochloride,metronidazole hydrochloride, pentamidine hydrochloride, gentamicinsulfate, kanamycin sulfate, lineomycin hydrochloride, methacyclinehydrochloride, methenamine hippurate, methenamine mandelate, minocyclinehydrochloride, neomycin sulfate, netilmicin sulfate, paromomycinsulfate, streptomycin sulfate, tobramycin sulfate, miconazolehydrochloride, amanfadine hydrochloride, amanfadine sulfate, triclosan,octopirox, parachlorometa xylenol, nystatin, tolnaftate and clotrimazoleand mixtures thereof.

Non-limiting examples of anti-oxidants that are usable in the context ofthe present invention include ascorbic acid (vitamin C) and its salts,ascorbyl esters of fatty acids, ascorbic acid derivatives (e.g.,magnesium ascorbyl phosphate, sodium ascorbyl phosphate, ascorbylsorbate), tocopherol (vitamin E), tocopherol sorbate, tocopherolacetate, other esters of tocopherol, butylated hydroxy benzoic acids andtheir salts, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid(commercially available under the trade name Trolox®), gallic acid andits alkyl esters, especially propyl gallate, uric acid and its salts andalkyl esters, sorbic acid and its salts, lipoic acid, amines (e.g.,N,N-diethylhydroxylamine, amino-guanidine), sulfhydryl compounds (e.g.,glutathione), dihydroxy fuimaric acid and its salts, lysine pidolate,arginine pilolate, nordihydroguaiaretic acid, bioflavonoids, curcumin,lysine, methionine, proline, superoxide dismutase, silymarin, teaextracts, grape skin/seed extracts, melanin, and rosemary extracts.

Non-limiting examples of antineoplastic agents usable in context of thepresent invention include daunorubicin, doxorubicin, idarubicin,amrubicin, pirarubicin, epirubicin, mitoxantrone, etoposide, teniposide,vinblastine, vincristine, mitomycin C, 5-FU, paclitaxel, docetaxel,actinomycin D, colchicine, topotecan, irinotecan, gemcitabinecyclosporin, verapamil, valspodor, probenecid, MK571, GF120918,LY335979, biricodar, terfenadine, quinidine, pervilleine A and XR9576.

Non-limiting examples of antidepressants usable in context of thepresent invention include norepinephrine-reuptake inhibitors (“NRIs”),selective-serotonin-reuptake inhibitors (SSRIs), monoamine-oxidaseinhibitors (MAOIs), serotonin-and-noradrenalin-reuptake inhibitors(“SNFIs”), corticotropin-releasing factor (CRF) antagonists,α-adrenoreceptor antagonists, NK1-receptor antagonists,5-HT_(1A)-receptor agonist, antagonists, and partial agonists andatypical antidepressants, as well as norepinephrine-reuptake inhibitorssuch as, but are not limited to amitriptyline, desmethylamitriptyline,clomipramine, doxepin, imipramine, imipramine-oxide, trimipramine;adinazolam, amiltriptylinoxide, amoxapine, desipramine, maprotiline,nortriptyline, protriptyline, amineptine, butriptyline, demexiptiline,dibenzepin, dimetacrine, dothiepin, fluacizine, iprindole, lofepramine,melitracen, metapramine, norclolipramine, noxiptilin, opipramol,perlapine, pizotyline, propizepine, quinupramine, reboxetine,tianeptine, and serotonin-reuptake inhibitors such as, but are notlimited to, binedaline, m-chloropiperzine, citalopram, duloxetine,etoperidone, femoxetine, fluoxetine, fluvoxamine, indalpine,indeloxazine, milnacipran, nefazodone, oxaflazone, paroxetine,prolintane, ritanserin, sertraline, tandospirone, venlafaxine andzimeldine.

Exemplary anti-dandruff ingredients usable in context of the presentinvention include, without limitation, zinc pyrithione, shale oil andderivatives thereof such as sulfonated shale oil, selenium sulfide,sulfur; salicylic acid, coal tar, povidone-iodine, imidazoles such asketoconazole, dichlorophenyl imidazolodioxalan, clotrimazole,itraconazole, miconazole, climbazole, tioconazole, sulconazole,butoconazole, fluconazole, miconazolenitrite and any possible stereoisomers and derivatives thereof such as anthralin, piroctone olamine(Octopirox), selenium sulfide, and ciclopirox olamine, and mixturesthereof.

Non-limiting examples of vitamins usable in context of the presentinvention include vitamin A and its analogs and derivatives: retinol,retinal, retinyl palmitate, retinoic acid, tretinoin, iso-tretinoin(known collectively as retinoids), vitamin E (tocopherol and itsderivatives), vitamin C (L-ascorbic acid and its esters and otherderivatives), vitamin B₃ (niacinamide and its derivatives), alphahydroxy acids (such as glycolic acid, lactic acid, tartaric acid, malicacid, citric acid, etc.) and beta hydroxy acids (such as salicylic acidand the like).

Non-limiting examples of dermatological active ingredients usable incontext of the present invention include jojoba oil and aromatic oilssuch as methyl salicylate, wintergreen, peppermint oil, bay oil,eucalyptus oil and citrus oils, as well as ammonium phenolsulfonate,bismuth subgallate, zinc phenolsulfonate and zinc salicylate.Non-limiting examples of antifungal agents include miconazole,clotrimazole, butoconazole, fenticonasole, tioconazole, terconazole,sulconazole, fluconazole, haloprogin, ketonazole, ketoconazole,oxinazole, econazole, itraconazole, terbinatine, nystatin andgriseofulvin.

Non-limiting examples of antihistamines usable in context of the presentinvention include chlorpheniramine, brompheniramine,dexchlorpheniramine, tripolidine, clemastine, diphenhydramine,promethazine, piperazines, piperidines, astemizole, loratadine andterfenadine.

Suitable hormones for use in the context of the present inventioninclude, for example, androgenic compounds and progestin compounds.

Representative examples of androgenic compounds include, withoutlimitation, methyltestosterone, androsterone, androsterone acetate,androsterone propionate, androsterone benzoate, androsteronediol,androsteronediol-3-acetate, androsteronediol-17-acetate,androsteronediol 3-17-diacetate, androsteronediol-17-benzoate,androsteronedione, androstenedione, androstenediol,dehydroepiandrosterone, sodium dehydroepiandrosterone sulfate,dromostanolone, dromostanolone propionate, ethylestrenol,fluoxymesterone, nandrolone phenpropionate, nandrolone decanoate,nandrolone furylpropionate, nandrolone cyclohexane-propionate,nandrolone benzoate, nandrolone cyclohexanecarboxylate,androsteronediol-3-acetate-1-7-benzoate, oxandrolone, oxymetholone,stanozolol, testosterone, testosterone decanoate, 4-dihydrotestosterone,5α-dihydrotestosterone, testolactone, 17α-methyl-19-nortestosterone andpharmaceutically acceptable esters and salts thereof, and combinationsof any of the foregoing.

Representative examples of progestin compounds include, withoutlimitation, desogestrel, dydrogesterone, ethynodiol diacetate,medroxyprogesterone, levonorgestrel, medroxyprogesterone acetate,hydroxyprogesterone caproate, norethindrone, norethindrone acetate,norethynodrel, allylestrenol, 19-nortestosterone, lynoestrenol,quingestanol acetate, medrogestone, norgestrienone, dimethisterone,ethisterone, cyproterone acetate, chlormadinone acetate, megestrolacetate, norgestimate, norgestrel, desogrestrel, trimegestone,gestodene, nomegestrol acetate, progesterone, 5α-pregnan-3β,20α-diolsulfate, 5α-pregnan-3β,20β-diol sulfate, 5α-pregnan-3β-ol-20-one,16,5α-pregnen-3β-ol-20-one, 4-pregnen-20β-ol-3-one-20-sulfate,acetoxypregnenolone, anagestone acetate, cyproterone, dihydrogesterone,flurogestone acetate, gestadene, hydroxyprogesterone acetate,hydroxymethylprogesterone, hydroxymethyl progesterone acetate,3-ketodesogestrel, megestrol, melengestrol acetate, norethisterone andmixtures thereof.

By selecting the appropriate carrier and optionally other ingredientsthat can be included in the composition, as is detailed hereinabove, thetellurium-containing compounds used in context of the present inventionmay be formulated into any form typically employed for topicalapplication. Hence, the formulations of the present invention can be,for example, in a form of a cream, an ointment, a paste, a gel, alotion, a milk, a suspension, an aerosol, a spray, a foam, a shampoo, ahair conditioner, a serum, a swab, a pledget, a pad, a patch and a soap.

Ointments are semisolid preparations, typically based on petrolatum orpetroleum derivatives. The specific ointment base to be used is one thatprovides for optimum delivery for the active agent chosen for a givenformulation, and, preferably, provides for other desired characteristicsas well (e.g., emolliency). As with other carriers or vehicles, anointment base should be inert, stable, nonirritating and nonsensitizing.As explained in Remington: The Science and Practice of Pharmacy, 19thEd., Easton, Pa.: Mack Publishing Co. (1995), pp. 1399-1404, ointmentbases may be grouped in four classes: oleaginous bases; emulsifiablebases; emulsion bases; and water-soluble bases. Oleaginous ointmentbases include, for example, vegetable oils, fats obtained from animals,and semisolid hydrocarbons obtained from petroleum. Emulsifiableointment bases, also known as absorbent ointment bases, contain littleor no water and include, for example, hydroxystearin sulfate, anhydrouslanolin and hydrophilic petrolatum. Emulsion ointment bases are eitherwater-in-oil (W/O) emulsions or oil-in-water (O/W) emulsions, andinclude, for example, cetyl alcohol, glyceryl monostearate, lanolin andstearic acid.

Lotions are preparations that are to be applied to the skin surfacewithout friction. Lotions are typically liquid or semiliquidpreparations in which solid particles, including the active agent, arepresent in a water or alcohol base. Lotions are typically preferred fortreating large body areas, due to the ease of applying a more fluidcomposition. Lotions are typically suspensions of solids, and oftentimescomprise a liquid oily emulsion of the oil-in-water type. It isgenerally necessary that the insoluble matter in a lotion be finelydivided. Lotions typically contain suspending agents to produce betterdispersions as well as compounds useful for localizing and holding theactive agent in contact with the skin, such as methylcellulose, sodiumcarboxymethyl-cellulose, and the like.

Creams are viscous liquids or semisolid emulsions, either oil-in-wateror water-in-oil. Cream bases are typically water-washable, and containan oil phase, an emulsifier and an aqueous phase. The oil phase, alsocalled the “internal” phase, is generally comprised of petrolatum and/ora fatty alcohol such as cetyl or stearyl alcohol. The aqueous phasetypically, although not necessarily, exceeds the oil phase in volume,and generally contains a humectant. The emulsifier in a creamformulation is generally a nonionic, anionic, cationic or amphotericsurfactant. Reference may be made to Remington: The Science and Practiceof Pharmacy, supra, for further information.

Pastes are semisolid dosage forms in which the bioactive agent issuspended in a suitable base. Depending on the nature of the base,pastes are divided between fatty pastes or those made from asingle-phase aqueous gels. The base in a fatty paste is generallypetrolatum, hydrophilic petrolatum and the like. The pastes made fromsingle-phase aqueous gels generally incorporate carboxymethylcelluloseor the like as a base. Additional reference may be made to Remington:The Science and Practice of Pharmacy, for further information.

Gel formulations are semisolid, suspension-type systems. Single-phasegels contain organic macromolecules distributed substantially uniformlythroughout the carrier liquid, which is typically aqueous, but also,preferably, contain an alcohol and, optionally, an oil. Preferredorganic macromolecules, i.e., gelling agents, are crosslinked acrylicacid polymers such as the family of carbomer polymers, e.g.,carboxypolyalkylenes that may be obtained commercially under thetrademark CARBOPOL™. Other types of preferred polymers in this contextare hydrophilic polymers such as polyethylene oxides,polyoxyethylene-polyoxypropylene copolymers and polyvinylalcohol;cellulosic polymers such as hydroxypropyl cellulose, hydroxyethylcellulose, hydroxypropyl methylcellulose, hydroxypropyl methylcellulosephthalate, and methyl cellulose; gums such as tragacanth and xanthangum; sodium alginate; and gelatin. In order to prepare a uniform gel,dispersing agents such as alcohol or glycerin can be added, or thegelling agent can be dispersed by trituration, mechanical mixing orstirring, or combinations thereof.

Sprays generally provide the active agent in an aqueous and/or alcoholicsolution which can be misted onto the skin for delivery. Such spraysinclude those formulated to provide for concentration of the activeagent solution at the site of administration following delivery, e.g.,the spray solution can be primarily composed of alcohol or other likevolatile liquid in which the active agent can be dissolved. Upondelivery to the skin, the carrier evaporates, leaving concentratedactive agent at the site of administration.

Foam compositions are typically formulated in a single or multiple phaseliquid form and housed in a suitable container, optionally together witha propellant which facilitates the expulsion of the composition from thecontainer, thus transforming it into a foam upon application. Other foamforming techniques include, for example the “Bag-in-a-can” formulationtechnique. Compositions thus formulated typically contain a low-boilinghydrocarbon, e.g., isopropane. Application and agitation of such acomposition at the body temperature cause the isopropane to vaporize andgenerate the foam, in a manner similar to a pressurized aerosol foamingsystem. Foams can be water-based or hydroalcoholic, but are typicallyformulated with high alcohol content which, upon application to the skinof a user, quickly evaporates, driving the active ingredient through theupper skin layers to the site of treatment.

Skin patches typically comprise a backing, to which a reservoircontaining the active agent is attached. The reservoir can be, forexample, a pad in which the active agent or composition is dispersed orsoaked, or a liquid reservoir. Patches typically further include afrontal water permeable adhesive, which adheres and secures the deviceto the treated region. Silicone rubbers with self-adhesiveness canalternatively be used. In both cases, a protective permeable layer canbe used to protect the adhesive side of the patch prior to its use. Skinpatches may further comprise a removable cover, which serves forprotecting it upon storage.

Compositions for topical or systemic application, which contain one ormore of the tellurium-containing compounds described herein andoptionally pharmaceutically acceptable carriers and excipients, areformulated as creams, lotions, ointments, gels, solutions, foams,mousses and the like (as is detailed hereinabove), using conventionalmethods (see, for example, Harry's Cosmeticology, Seventh Edition,Edited by J B Wilkinson and R J Moore, Longmann Scientific & Technical,1982, Chapter 13 “The Manufacture of Cosmetics” pages 757-799; and“Remington's Pharmaceutical Sciences,” Mack Publishing Co., Easton, Pa.,latest edition).

The compositions of the present invention may be packed or presented inany convenient way. For example, they may be packed in a tube, a bottle,or a pressurized container, using techniques well known to those skilledin the art and as set forth in reference works such as Remington'sPharmaceutical Science 15^(th) Ed. It is preferred that the packaging isdone in such a way so as to minimize contact of the unused compositionswith the environment, in order to minimize contamination of thecompositions before and after the container is opened.

The formulations are preferably identified in print, in or on thepackaging material, for use in the treatment of any medical conditionsin which topical application of a tellurium-containing compound isbeneficial.

An exemplary formulation according to the present embodiments comprisesa combination of various polyethylene glycols propylene glycol and/orDMSO, PHOSAL®50PG™ and Brij 72. Formulations comprising these componentswere found to be homogeneous and had very fine particles as seen underpolarized light (see, for example, formulation PGB3 in FIGS. 3A and 3B),and were further found to be stable and to withstand a series ofstability tests while not separating or discoloring, and further whilemaintaining their viscosity at ambient temperature.

It has thus been demonstrated herein for the first time thattellurium-containing compounds can be formulated in a topical aqueousformulation, also at relatively high concentrations, while maintainingtheir chemical, physical and visual stability, as well as an optimalstability, resulting in a smooth and pleasant feel.

Being hydrophilic, these formulations are non-greasy, and will not stainthe cloths or garments coming in contact with them.

Thus, according to a preferred embodiment of the present invention, anyof the above-detailed formulations is provided as a hydrophilicformulation.

According to another preferred embodiment of the present invention, anyof the above-detailed formulations is provided as a washableformulation.

These formulations are further characterized by maintaining theirviscosity upon various conditions.

Thus, according to a preferred embodiment of the present invention, eachof the formulations described herein are characterized by a viscosity inthe range of from 1,000 to 1,000,000 cpi at room temperature,preferably, from about 3,000 to about 30,000 cpi at room temperature.

As used herein, the term “about” describes ±10%.

In each of the formulations described herein, a concentration of thetellurium-containing compound in the formulation preferably ranges fromabout 0.01 weight percent to about 50 weight percents, more preferablyfrom about 1 weight percent to about 20 weight percents, of the totalweight of the composition. In certain embodiments, thetellurium-containing compound in the formulation is present in an amountup to about 25 weight percent.

Thus, depending on the condition being treated and the composition form,the concentration of the tellurium-containing compound can be, forexample, at least 0.01 weight percent, at least 0.05 weight percent, atleast 0.1 weight percent, at least 0.5 weight percent, at least 1 weightpercent, at least 2 weight percents, at least 3 weight percents, atleast 4 weight percents or at least 5 weight percents. Higherconcentrations can also be used and thus can be, for example, at least 5weight percents, at least 6 weight percents, at least 7 weight percents,at least 8 weight percents, at least 9 weight percents or at least 10weight percents and up to at least 20 weight percents, at least 25weight percents, at least 30 weight percents, at least 40 weightpercents, at least 50 weight percents, at least 60 weight percents, atleast 70 weight percents, at least 80 weight percents, and can be up toabout 85 weight percents of the total weight of the composition.

In an exemplary formulation, the tellurium-containing compound ispresent in a concentration of 12 weight percents. In another exemplaryformulation, the tellurium-containing compound is present in aconcentration of 15 weight percents.

As described in the Background section hereinabove, topical formulationsare often characterized by high concentrations of the active ingredient,typically higher than 1 weight percent, and preferably higher than 5weight percents, which are required to provide the desired therapeuticeffect. To date, tellurium-containing compositions having such arelatively high concentration of the tellurium-containing compound werecharacterized by insufficient suitability for topical applications interms of stability and appearance. As shown herein, tellurium-containingtopical formulations can be readily obtained and are characterized by ahigh stability even at high concentrations typical of topicalformulations.

Thus, further according to the present invention there is provided achemically and physically stable formulation for topical application,which comprises a tellurium-containing compound as described herein, ina concentration of at least 3 weight percents, and a pharmaceuticallyacceptable carrier. Often in the treatment of psoriasis and related skindisorders the active ingredient comprises 3-4 weight percents of theformulation.

Preferably the formulation comprises at least 3 weight percents, morepreferably at least 4 weight percents, more preferably at least 5 weightpercents, more preferably at least 6 weight percents, more preferably atleast 7 weight percents, more preferably at least 8 weight percents,more preferably at least 9 weight percents, more preferably at least 10weight percents, more preferably at least 11 weight percents, morepreferably at least 12 weight percents, more preferably at least 13weight percents, more preferably at least 14 weight percents, morepreferably at least 15 weight percents, more preferably at least 16weight percents, more preferably at least 17 weight percents, morepreferably at least 18 weight percents, more preferably at least 19weight percents, and more preferably at least 20 weight percents,

The formulations of the present invention may be manufactured byprocesses well known in the art, e.g., by means of conventional mixing,dissolving, granulating, dragee-making, levigating, emulsifying,encapsulating, entrapping or lyophilizing processes.

According to another aspect of the present invention, the formulationsdescribed herein are easily prepared by mixing a tellurium-containingcompound and a carrier, as these are defined herein. Preferably, themixing is conducted at a temperature range of about 10° C. to about 100°C.

As exemplified in the Background section hereinabove,tellurium-containing compounds were found exceptionally effective intreating skin and mucosal membrane ailments, caused by HPV (WO2005/069735, supra), in the treatment or prevention of alopecia andother conditions associated with hair loss (U.S. Provisional PatentApplication No. 60/610,660, supra, U.S. Pat. Nos. 6,552,089 and5,262,149 supra), in the treatment of BCC and AK (U.S. ProvisionalPatent Application No. 60/716,923, supra), in the treatment of damagescaused by exposure to UV irradiation (U.S. Provisional PatentApplication No. 60/716,924, supra), psoriasis (U.S. Pat. No. 6,472,381),atopic dermatitis, Kaposi's sarcoma, scleroderma, burns, scarring (seeU.S. Provisional Patent Application No. 60/610,660) and metastaticmelanoma (Sun et al. 1996, supra).

Thus, medical conditions treatable by the tellurium-containingformulations include, for example, scleroderma, psoriasis, atopicdermatitis, scarring, a human papilloma virus related skin and/ormucosal membrane ailment, condilloma, warts, alopecia, hair loss,metastatic melanoma, basal cell carcinoma, actinic keratosis and UV skindamage.

The term “scleroderma” refers to a disease of the skin and connectivetissue that causes the skin to become hard and can result in hair loss.

The term “atopic dermatitis” is also known as eczema, and refers to anallergic skin disorder that us causes the skin to itch, scale and flake.

The term “scarring” refers to a biologic process of wound repair in theskin and other tissues of the body. It considered that almost everywound (e.g. after accident, disease, or surgery) results in some degreeof scarring.

The term “melanoma” refers to a malignant tumor of the skin, which oftenappears as a slightly raised irregular brownish tumor.

The term “Kaposi's sarcoma” (KS) refers to a tumor which appears as aflat or raised purplish patch on the skin or mucous membranes (in themouth, rectum, or vagina). KS may also spread to internal organs, likethe esophagus, intestines, colon, or lungs.

As used herein, the phrase “a skin or mucosal membrane ailment caused bya HPV”, which also referred to herein interchangeable as “HPV-causedailment”, encompasses any ailment that is associated, either directly orindirectly, with any type of HPV.

To date, there are more than seventy identified distinct types of HPVs.These different types have been subdivided into two large categories:cutaneous and mucosal. Since, as is further discussed hereinabove, someHPV-caused ailments may develop into cervical cancer, these differentvirus types have been further categorized in this respect by their riskgrade and therefore include low-risk HPV types, moderate-risk HPV typesand high-risk HPV types.

According to still further features in the described preferredembodiments the skin or mucosal membrane ailment is such as, but notlimited to verruca vulgaris, plantar warts, palmar warts, periungalwarts, planar warts, mosaic warts, genital warts, venereal warts(condylomata acuminata), butcher's warts, malignant epidermodyspasiaverruciformis, advanced intraepithelial dysplasia, cervical cancer,mepidermodysplasia verruciformis, cutaneous warts in immunosuppressivepatients, laryngeal papillomas and oral papilloma.

However, it is expected that during the life of this patent manyrelevant medical conditions will be found to be treatable bytellurium-containing topical formulations, and thus the scope of thephrase “for use in the treatment of any medical conditions in whichtopical application of a tellurium-containing compound is beneficial” isintended to include all such new medical conditions a priori.

As used herein, the phrase “tellurium-containing compound” encompassesany compound that includes one or more tellurium atoms.

The tellurium-containing compound may be an inorganic compound or anorganic compound.

Inorganic tellurium-containing compounds include, for example, telluriumdioxide (TeO₂) per se.

Organic tellurium-containing compounds may be in the form of an organiccomplex such as, for example, a TeO₂ complex with citric acid orethylene glycol, which may form TeO₂ as an end product in aqueoussolutions. A representative example of the latter is the complexTeO₂HOCH₂CH₂OHNH₄Cl. Otherwise, the tellurium-containing compoundsdescribed herein include one or more tellurium atoms and one or moreorganic moieties that are attached thereto, for example, ammonium salts,or any other salts, of halogenated tellurium-containing compounds havinga bidentate cyclic moiety attached to the tellurium atom. The bidentatecyclic moiety is preferably a di-oxo moiety having two oxygen atomsattached to the tellurium atom. The bidentate cyclic moiety can be adi-thio moiety, in which two sulfur atoms are attached to the telluriumatom.

Preferred compounds in this category are collectively represented by thegeneral Formula I:

In the general Formula I above, each of t, u and v is independently 0 or1, such that the compound may include a five-membered ring, asix-membered ring, or a seven-membered ring. Preferably, each of t, uand v is 0, such that the compound includes a five-membered ring.

X is a halogen atom, as described hereinabove, and is preferably chloro.

In some embodiments, Y is a cation. In a preferred embodiment, Y isselected from the group consisting of ammonium, phosphonium, potassium,sodium and lithium, and is preferably ammonium.

Each of R₁-R₁₀ is independently selected from the group consisting ofhydrogen, hydroxyallcyl, hydroxy, thiohydroxy, alkyl, alkenyl, alkynyl,alkoxy, thioalkoxy, halogen, haloalkyl, carboxy, carbonyl,alkylcarbonylalkyl, alkoxy, carboxyalkyl, acyl, amido, cyano,N-monoalkylamidoalkyl, N,N-dialkylamidoalkyl, cyanoalkyl, alkoxyalkyl,carbamyl, cycloalkyl, heteroalicyclic, sulfonyl, sulfinyl, sulfate,amine, aryl, heteroaryl, phosphate, phosphonate and sulfonamido.

As used herein, the term “alkyl” refers to a saturated aliphatichydrocarbon including straight chain and branched chain groups.Preferably, the alkyl group has 1 to 20 carbon atoms. More preferably,the alkyl is a medium size alkyl having 1 to 10 carbon atoms. Mostpreferably, unless otherwise indicated, the alkyl is a lower alkylhaving 1 to 5 carbon atoms. The alkyl group may be substituted orunsubstituted. When substituted, the substituent group can be asdescribed herein for R₁.

As used herein, the term “hydroxyalkyl” refers to an alkyl, as this termis defined herein, substituted by a hydroxy group, as defined herein,and includes, for example, hydroxymethyl, hydroxyethyl, hydroxypropyland hydroxy-n-butyl.

As used herein, the term “halogen”, which is also referred to hereininterchangeably as “a halogen atom” or “halo”, includes chloro (Cl),bromo (Br), iodo (I) and fluoro (F).

The term “haloalkyl” refers to an alkyl as this term is defined herein,substituted by a halogen, as defined herein, and includes, for example,chloromethyl, 2-iodoethyl, 4-bromo-n-butyl, iodoethyl, 4-bromo-n-pentyland the like.

The term “alkanoyloxy” refers to a carbonyl group, as define herein andincludes, for example, acetyl, propionyl, butanoyl and the like.

The term “carboxyalkyl” refers to an alkyl, as this term is definedherein, substituted by a carboxy group, as defined herein, and includes,for example, carboxymethyl, carboxyethyl, ethylenecarboxy and the like.

The term “alkylcarbonylallcyl” refers to an alkyl, as this term isdefined herein, substituted by a carbonyl group, as defined herein, andincludes, for example, methanoyhnethyl, ethanoylethyl and the like.

The term “amidoalkyl” refers to an alkyl, as this term is definedherein, substituted by an amide group, as defined herein, and includes,for example, —CH₂CONH₂; —CH₂CH₂CONH₂; —CH₂CH₂CH₂CONH₂ and the like.

The term “cyanoalkyl” refers to an alkyl, as this term is definedherein, substituted by an cyano group, as defined herein, and includes,for example, —CH₂CN; —CH₂CH₂CN; —CH₂CH₂CH₂CN and the like.

The term “N-monoalkylamidoalkyl” refers to an alkyl, as this term isdefined herein, substituted by an amide group, as defined herein, inwhich one of R′ and R″ is an alkyl, and includes, for example,—CH₂CH₂CONHCH₃, and —CH—₂CONHCH₂CH₃.

The term N,N-dialkylamidoalkyl refers to an alkyl, as this term isdefined herein, substituted by an amide group, as defined herein, inwhich both R′ and R″ are alkyl, and includes, for example,—CH₂CON(CH₃)₂; CH₂CH₂CON(CH₂—CH₃)₂ and the like.

A “cycloalkyl” group refers to an all-carbon monocyclic or fused ring(i.e., rings which share an adjacent pair of carbon atoms) group whereinone of more of the rings does not have a completely conjugatedpi-electron system. Examples, without limitation, of cycloalkyl groupsare cyclopropane, cyclobutane, cyclopentane, cyclopentene, cyclohexane,cyclohexadiene, cycloheptane, cycloheptatriene, and adamantane. Acycloalkyl group may be substituted or unsubstituted. When substituted,the substituent group can be as described herein for R1.

An “alkenyl” group refers to an alkyl group which consists of at leasttwo carbon atoms and at least one carbon-carbon double bond.

An “alkynyl” group refers to an alkyl group which consists of at leasttwo carbon atoms and at least one carbon-carbon triple bond.

An “aryl” group refers to an all-carbon monocyclic or fused-ringpolycyclic (i.e., rings which share adjacent pairs of carbon atoms)groups having a completely conjugated pi-electron system. Examples,without limitation, of aryl groups are phenyl, naphthalenyl andanthracenyl. The aryl group may be substituted or unsubstituted. Whensubstituted, the substituent group can be as described herein for R1.

A “heteroaryl” group refers to a monocyclic or fused ring (i.e., ringswhich share an adjacent pair of atoms) group having in the ring(s) oneor more atoms, such as, for example, nitrogen, oxygen and sulfur and, inaddition, having a completely conjugated pi-electron system. Examples,without limitation, of heteroaryl groups include pyrrole, faran,thiophene, imidazole, oxazole, thiazole, pyrazole, pyridine, pyrimidine,quinoline, isoquinoline and purine. The heteroaryl group may besubstituted or unsubstituted. When substituted, the substituent groupcan be as described herein for R1.

A “heteroalicyclic” group refers to a monocyclic or fused ring grouphaving in the ring(s) one or more atoms such as nitrogen, oxygen andsulfur. The rings may also have one or more double bonds. However, therings do not have a completely conjugated pi-electron system. Theheteroalicyclic may be substituted or unsubstituted. When substituted,the substituent group can be as described herein for R1.

A “hydroxy” group refers to an —OH group.

An “alkoxy” group refers to both an —O-alkyl and an —O-cycloalkyl group,as defined herein.

An “aryloxy” group refers to both an —O-aryl and an —O-heteroaryl group,as defined herein.

A “thiohydroxy” group refers to a —SH group.

A “thioalkoxy” group refers to both an —S-alkyl group, and an—S-cycloalkyl group, as defined herein.

A “thioaryloxy” group refers to both an —S-aryl and an —S-heteroarylgroup, as defined herein.

A “carbonyl” group refers to a —C(═O)—R′ group, where R′ is hydrogen,alkyd, alkenyl, cycloalkyl, aryl, heteroaryl (bonded through a ringcarbon) or heteroalicyclic (bonded through a ring carbon) as definedherein.

A “thiocarbonyl” group refers to a —C(═S)—R′ group, where R′ is asdefined herein.

A “carboxy” group refers to a —C(═O)—O—R′ or a —O—C(═O)—R′ group, whereR′ is as defined herein.

A “sulfinyl” group refers to an —S(═O)—R′ group, where R′ is as definedherein.

A “sulfonyl” group refers to an —S(═O)₂—R′ group, where R′ is as definedherein.

A “sulfate” group refers to a —O—S(═O)₂—OR′ group, where R′ is asdefined herein.

A “sulfonamido” group refers to a —S(═O)₂—NR′R″ group or a R′S(═O)₂—NR″,with R′ is as defined herein and R″ is as defined for R′.

A “carbamyl” or “carbamate” group refers to an —OC(═O)—NR′R″ group or aR″OC(═O)—NR′— group, where R′ and R″ are as defined herein.

A “thiocarbamyl” or “thiocarbamate” group refers to an —OC(═S)—NR′R″group or an R″OC(═S)NR′— group, where R′ and R″ are as defined herein.

An “amino” group refers to an —NR′R″ group where R′ and R″ are asdefined herein.

An “amido” group refers to a —C(═O)—NR′R″ group or a R′C(═O)—NR″ group,where R′ and R″ are as defined herein.

A “nitro” group refers to an —NO₂ group.

A “cyano” group refers to a —C═N group.

The term “phosphonyl” describes a —O—P(═O)(OR′)(OR″) group, with R′ andR″ as defined hereinabove.

The term “phosphinyl” describes a —PR′R″ group, with R′ and R″ asdefined hereinabove.

As cited hereinabove, the compounds in this category are salts oforganic tellurium-containing compounds. The salts can be, for example,ammonium salts, phosphonium salts and alkaline salts such as potassiumsalts, sodium salts, lithium salts and the like.

Hence, Y in Formula I above can be a phosphonium group, as definedherein, an ammonium group, as defined herein, potassium (K⁺), sodiumNa⁺) or lithium (Li⁺).

As used herein, the term “phosphonium” describes a —P⁺R′R″R′″ group,with R′ and R″ as defined herein and R′″ is as defined for R′. The term“phosphonium”, as used herein, further refers to a —P⁺R₆ group, whereineach of the six R substituents is independently as defined herein for R,R″ and K′″.

The term “ammonium” describes a —N⁺R′R″R′″ group, with R′, R″ and R′″ asdefined herein.

More preferred compounds in this category include compounds having thegeneral Formula I described above, in which Y is ammonium orphosphonium, t, u and v are each 0, and each of R₁, R₈, R₉ and R₁₀ isindependently hydrogen or alkyl. These compounds can be represented bythe following structure:

wherein each of R₁, R₈, R₉ and R₁₀ is independently hydrogen or alkyl,whereas a preferred alkyl is methyl, and X is halogen, preferablychloro.

The presently most preferred compound for use in the context of thepresent invention has the following structure:

This compound is ammonium trichloro(dioxyethylene-O,O′)tellurate, whichis also referred to herein and in the art as AS101.

Additional representative examples of organic tellurium-containingcompound that are suitable for use in the context of the presentinvention include halogenated tellurium having a bidentate cyclic moietyattached to the tellurium atom. The bidentate cyclic moiety ispreferably a di-oxo ligand having two oxygen atoms attached to thetellurium atom. Alternatively, the bidentate cyclic moiety can be adi-thio ligand, in which two sulfur atoms are attached to the telluriumatom.

Preferred compounds in this category can be represented by the generalFormula II:

wherein t, u, v, X and R₁-R₁₀ are as defined hereinabove.

More preferred compounds are those in which t, u, and v are each 0, andX is chloro, such as, but not limited to, the compound having thefollowing structure:

The above compound is also known and referred to herein as AS103.

The organic tellurium-containing compounds having Formulae I and II canbe readily prepared by reacting tetrahalotelluride such as TeCl₄ with adihydroxy compound, as is described in detail in U.S. Pat. Nos.4,752,614, 4,761,490, 4,764,461 and 4,929,739, which are incorporated byreference as if fully set forth herein.

Additional representative examples of organic tellurium-containingcompounds that are suitable for use in the context of the presentinvention include compounds in which two bidentatic cyclic moieties areattached to the tellurium atom. Preferably, each of the cyclic moietiesis a di-oxo moiety. Alternatively, one or more of the cyclic moieties isa di-thio moiety.

Preferred compounds in this category are collectively represented by thegeneral Formula III:

In the general Formula III above, each of j and k is independently aninteger from 0 to 4, such that the compound may include a five-memberedring, a six-membered ring, a seven-membered ring, an eight-membered ringand/or a nine-membered ring. Preferably, each of j and k is an integerfrom 0 to 2, such that the compound includes a five-membered ring, asix-membered ring and/or a seven-membered ring, More preferably, each ofj and k is 0.

R₁-R₁₂ are as defined hereinabove for R₁-R₁₀.

More preferred compounds in this category are those in which j and k areeach 0, and R₃, R₄, R₉ and R₁₀ are each hydrogen, having the followingstructure:

wherein each of R₁₁-R₁₄ is independently selected from the groupconsisting of hydrogen, hydroxyalkyl, hydroxy, thiohydroxy, alkyl,alkenyl, alkynyl, alkoxy, thioalkoxy, halogen, haloalkyl, carboxy,carbonyl, alkylcarbonylalkyl, alkoxy, carboxyalkyl, acyl, amido, cyano,N-monoalkylamidoalkyl, N,N-dialkylamidoalkyl, cyanoalkyl, alkoxyalkyl,carbamyl, cycloalkyl, heteroalicyclic, sulfonyl, sulfinyl, sulfate,amine, aryl, heteroaryl, phosphate, phosphonate and sulfonamido, asthese terms are defined herein.

The most preferred compound in this category is a compound in which eachof R₁₁-R₁₄ is hydrogen. This compound is also known as AS102.

Additional representative examples of organic tellurium-containingcompounds that are suitable for use in the context of the presentinvention include the recently disclosed ditellurium compounds havinggeneral Formula IV:

wherein each of R₁₅-R₂₂ is independently selected from the groupconsisting of hydrogen, hydroxyalkyl, hydroxy, thiohydroxy, alkylalkenyl, alkynyl, alkoxy, thioalkkoxy, halogen, haloalkyl, carboxy,carbonyl, alkylcarbonylalkyl, alkoxy, carboxyalkyl, acyl, amido, cyano,N-monoalkylamidoalkyl, N,N-dialkylamidoalkyl, cyanoalkyl, alkoxyalkyl,carbamyl, cycloalkyl, heteroalicyclic, sulfonyl, sulfinyl, sulfate,amine, aryl, heteroaryl, phosphate, phosphonate and sulfonamido, asthese terms are defined herein; and

m and n are each an integer from 0 to 3.

Preferred compounds in this category are those in which m and n are each0.

The presently most preferred compound in this family is a compound inwhich R₁₅, R₁₈, R₁₉ and R₂₂ are all hydrogen, referred to hereinafter asSAS, and which has the following structure:

According to a most preferred embodiment of the present invention, thetellurium-containing compound is of Formula 1, most preferably, in whichY is ammonium, t, u and v are each 0, and each of R₁, R₈, R₉ and R₁₀ isindependently methyl and X is chloro, also known as AS101.

As demonstrated in the Examples section which follows, topicalformulations comprising AS101, as an exemplary tellurium-containingcompound, were formed (Example 3, formulation PGB3) and were found to bewell solubilized (FIGS. 3A and 3B) as well as highly stable, upon beingsubjected to a series of thermal stability, visual and centrifugationtests.

Additional objects, advantages, and novel features of the presentinvention will become apparent to one ordinarily skilled in the art uponexamination of the following examples, which are not intended to belimiting. Additionally, each of the various embodiments and aspects ofthe present invention as delineated hereinabove and as claimed in theclaims section below finds experimental support in the followingexamples.

EXAMPLES Materials and Methods

AS101 was supplied by M. Albeck from the chemistry department at BarIlan University, in three forms: as a powder, as a 20% solution indimethyl sulfoxide (DMSO) and as an ointment containing the DMSOsolution in combination with petroleum jelly.

Microscopic Evaluation of Samples and Polarized Light Crystallography:Formulation Stability Measurements

Thermal Stability:

each formulation sample was placed in a plastic eppendorf tube androtated each day between −10° C. and 40° C. four times, each cyclelasted 48 hours. Each sample was further placed in a 40° C. stabilitychamber for 90 days for an accelerated test.

Centrifugation:

each formulation sample was placed in a plastic eppendorf tube andcentrifuged for 10 minutes at 3,000 RPM and then for 10 minutes at10,000 RPM.

Example 1 Characterization of AS101 Powder, Solution and Ointment

In order to evaluate the effect of the present formulations of AS101 onits crystallinity and solubility, three samples of AS101 were tested: apowder, a 20% (by weight) solution in DMSO and an ointment containingthe DMSO solution in combination with petroleum jelly.

FIGS. 1A-B present images of the content and packaging components of thecontainers in which the AS101 powder (FIG. 1A) and the 20% AS101 20%solution in DMSO (FIG. 1B) were provided, upon 30 days of storage atambient temperature.

Samples were further characterized by polarized light and the obtainedimages 5 are presented in FIGS. 2A-B.

AS101 Powder:

The white crystalline coarse powder was placed in a scintillation glassbottle with a non-sealed cap. After storage, the aluminum laminate capwas examined and appeared to be chemically and physically decomposed,with black particles of its internal lining falling into the powder(FIG. 1A). The AS101 powder was characterized as having particles ofabout 20-40 microns in diameter, and distinct crystals producingbirefrigerence under polarized light, as seen in FIG. 2A.

AS101 Solution in DMSO:

A 20% (by weight) solution of AS101 in DMSO was prepared. The solutionappeared as a yellow liquid with a cloudy dispersion evolving uponmixing. After placing it in a scintillation glass bottle with anon-sealed cap, and re-examining the aluminum laminate cap afterstorage, decomposition was observed, as can be seen in FIG. 1B. As shownin FIG. 2B, no crystals were detected under polarized light. However,some unidentified particles were observed.

AS101 Ointment:

A 20% solution of AS101 in DMSO was mixed with petroleum jelly to yielda white waxy material having a small amount of liquid on top. FIGS. 2Cand 2D show two samples of the AS101 ointment under polarized light,confirming that AS101 was solubilized in DMSO but was not solubilized inthe DMSO/petroleum jelly ointment, re-crystallizing into anotherpolymorphic type.

Example 2 AS101 Solubility Profile

In a search for an improved formulation for topical application, thesolubility and stability (by coloration detection) of AS101 in varioushydrophilic and lipophilic solvents were determined. Since it iscommonly known that topically applied formulations have better skinabsorption and feel when the active pharmaceutical ingredient issolubilized or is in a molecular form, a desirable topical formulationshould be characterized by high solubility and/or dispersability of theactive ingredient therein.

Thus, solutions containing 10% by weight of AS101 in each solvent, wereprepared by mixing AS101 in the solvent at ambient temperature. Thesolubility and coloration results, as observed after 24 hours, arepresented in Table 1 below.

TABLE 1 Solvent Solubility Coloration DMSO Yes No Butyleneglycol Yes NoPEG 400 Yes No PEG 200 Yes No Glycofurol Yes No Propylene Glycol Yes NoTranscutol Yes No IPM No No Mineral oil No No MCT oil No No Arlamol E NoNo Hexylene glycol No No DMI No No Alkyl benzoate No No 1% acetic acidNo No Silicone oil No Black

As shown in Table 1, AS101 was well solubilized in amphiphilic glycolicsolvents such as PEG, butyleneglycol, gycofurol, propylene glycol andTRANSCUTOL (diethylene glycol mononethyl ether), while no precipitationor re-crystallization of AS101 was observed during the tested period.

Furthermore, solvents such as silicone oil and hydroxycellulose, whichare commonly-used inactive ingredients that improve the skin feeling ofcosmetic formulations, provide topical formulations with beneficialproperties such as pleasant skin feeling, were found incompatible due tounacceptable solution coloration.

Since AS101 is well solubilized in various PEGs and does not precipitateor re-crystallize at ambient temperature, further studies have focusedon the use of PEG mixtures as an exemplary carrier of choice.

Example 3 AS101 Formulations

AS101 formulations were developed based on the solubilization of AS101in a mixture of PEG solvents, PEG 200 and PEG 400, whereas theconcentration of each PEG solvent was selected so as to comply with theinactive ingredients guideline limits as published by the FDA. PEG 4000was added to modify the viscosity of the formulation to a topical use.

In one exemplary formulation, propylene glycol and PHOSAL® 50PG™ wereadded. Propylene glycol was also found to stabilize the formulation.

Such an Exemplary formulation (hereinafter termed PGB3) is presented inTable 2 below:

TABLE 2 Component Weight % Proposed Function AS101 12.00 Activeingredient PEG-400 39.00 Solvent/carrier PEG-200 30.00 Solvent/carrierPEG-4000 10.00 Thickener Propylene glycol 5.00 Co-solvent PHOSAL ® 50PG2.00 Skin penetrant Brij 72 2.00 Stabilizer Total 100.00

All glass or Teflon beakers, stirrers and mixer heads were used in thepreparation of AS101 formulations. PEG-400, PEG-200 and propylene glycolwere heated in a glass beaker on a steam bath to 80° C.-85° C., whilemoderately mixing. AS101 was then added, while moderately mixing toensure visual turbulence. Mixing was continued until AS101 wascompletely dissolved, Brij and PEG-4000 were added thereafter, andfurther mixing was effected until a homogenous solution was observed.The mixture was then removed from the steam bath and was left to cooldown, while stirring was continued. At about 50° C., PHOSAL® was addedand mixing was continued until a homogeneous solution was obtained. Theobtained formulation was stored in plastic, metal-free tubes/closures.

In an alternative procedure, propylene glycol was first added to AS101,while moderately mixing to ensure visual turbulence. Mixing wascontinued until AS101 was completely dissolved, Brij and PEGS were addedthereafter, and further mixing was effected until a homogenous solutionwas observed.

Upon heating the mixture of AS101 and propylene glycol, no change wasobserved.

A similar placebo formulation (hereinafter termed PGB3P) was prepared ina similar manner, by not adding the AS101 to the mixture.

The PGB3 formulation was homogeneous and had very fine and uniformtexture as seen under polarized light (FIGS. 3A and 3B). The PGB3formulation was visually stable and did not separate or discolorthroughout the various stability tests and maintained its viscosity atambient temperature.

The formulation was subjected to Freeze-Thaw-Cycle (FTC), Centrifugationand Accelerated Temperature stability tests, as described hereinabove.The PGB3 formulation was visually stable and did not separate or changeits color during all the stability tests. Product viscosity was retainedat ambient temperature following the stability tests.

The AS101 formulation did not react with phenol-epoxy internal liner ofaluminum tube for 30 days at 40° C., but reacted immediately with thealuminum of the tube opening as soon as the tube was punctured open withthe plastic cap and first dispensing, in a non-reversible manner.

An additional exemplary AS101 formulation, containing 15% by weightAS101, was similarly prepared, using a mixture of PEG solvents, PEG 200,PEG 400 and PEG 4000, as described herein, and DMSO. After dissolvingAS101 in the mixture of PEG and DMSO, PHOSAL® 50PG and Brij 72 wereadded. The formulation remained stable upon storage for 3 months days atroom temperature.

The following describes additional exemplary formulations according tothe present embodiments:

Component Weight % Function AS101 12.00 Active ingredient PEG-400 39.00Solvent/carrier PEG-200 30.00 Solvent/carrier PEG-4000 10.00 ThickenerDMSO 5.00 Co-solvent PHOSAL ® 50PG 2.00 Skin penetrant Brij 72 2.00Stabilizer Total 100.00

Component Weight % Function AS101 12.00 Active ingredient PEG-400 34.00Solvent/carrier PEG-200 30.00 Solvent/carrier PEG-4000 10.00 ThickenerPropylene glycol 5.00 Co-solvent DMSO 5.00 Co-solvent PHOSAL ® 50PG 2.00Skin penetrant Brij 72 2.00 Stabilizer Total 100.00

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination.

Although the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, it is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims. All publications, patents and patentapplications mentioned in this specification are herein incorporated intheir entirety by reference into the specification, to the same extentas if each individual publication, patent or patent application wasspecifically and individually indicated to be incorporated herein byreference. In addition, citation or identification of any reference inthis application shall not be construed as an admission that suchreference is available as prior art to the present invention.

What is claimed is:
 1. A highly stable formulation for topicalapplication, comprising a tellurium-containing compound in an amount ofabout 12 to about 35 weight percent of the formulation and having atleast one tellurium dioxo moiety and a pharmaceutically acceptablecarrier, wherein: said carrier comprises DMSO and at least onepolyethylene glycol solvent; said DMSO is in an amount between about 1%and about 10% by weight of the formulation; the formulation ischemically and physically stable upon storage at room temperature for atleast 30 days; and said tellurium-containing compound is soluble,dispersible and/or suspendable in said at least one polyethylene glycolsolvent at a concentration of about 10 weight percent and is selectedfrom the group consisting of tellurium dioxide (TeO₂), a complex ofTeO₂, a compound having general Formula I:

a compound having general Formula II:

a compound having general Formula III:

and a compound having general Formula IV:

wherein: each oft, u and v is independently 0 or 1; each of m and n isindependently an integer from 0 to 3; each of j and k is independentlyan integer from 0 to 4; Y is a cation; X is a halogen atom; and each ofR₁-R₂₂ is independently selected from the group consisting of hydrogen,hydroxyalkyl, hydroxy, thiohydroxy, alkyl, alkenyl, alkynyl, alkoxy,thioalkoxy, halogen, haloalkyl, carboxy, carbonyl, alkylcarbonylalkyl,carboxyalkyl, acyl, amido, cyano, N-monoalkyl amidoalkyl,N,N-dialkylamidoalkyl, cyanoalkyl, alkoxyalkyl, carbamyl, cycloalkyl,heteroalicyclic, sulfonyl, sulfinyl, sulfate, amine, aryl, heteroaryl,phosphate, phosphonate and sulfoneamido.
 2. The formulation of claim 1,wherein said carrier is selected such that the formulation is stableupon storage for at least 6 months at room temperature.
 3. Theformulation of claim 1, wherein said carrier is selected such that theformulation is stable upon storage at 40° C. for at least 30 days. 4.The formulation of claim 1, wherein said carrier is selected such thatthe formulation is stable upon storage at 40° C. for at least 60 days.5. The formulation of claim 1, wherein said carrier is selected suchthat the formulation is stable upon storage at 40° C. for at least 90days.
 6. The formulation of claim 1, wherein said carrier is selectedsuch that the formulation is stable upon cycling at a temperature thatalternates at least 3 times from about −10° C. to about 40° C. aboutevery 48 hours.
 7. The formulation of claim 1, wherein said carrier isselected such that the formulation is stable upon centrifugation atabout 3,000 RPM for 10 minutes and then at 10,000 RPM for additional 10minutes.
 8. The formulation of claim 1, wherein said at least onepolyethylene glycol has an average molecular weight that ranges fromabout 100 Da to about 10000 Da.
 9. The formulation of claim 8, whereinsaid carrier comprises a mixture of polyethylene glycols selected so asto provide the formulation with a desired consistency applicable fortopical formulation and/or to provide a formulation that is convenientlyapplied and/or absorbed.
 10. The formulation of claim 1, wherein saidcarrier further comprises at least one ingredient selected from thegroup consisting of a stabilizer, a penetration enhancer, a humectant, adeodorant, an aroma modifier, an antiperspirant, a sun screening agent,a sunless tanning agent, a hair conditioning agent, a pH adjustingagent, a sun blocking agent, a chelating agent, a preservative, anemulsifier, an occlusive agent, an emollient, a thickener, asolubilizing agent, an anti-irritant, a colorant, a propellant and asurfactant.
 11. The formulation of claim 1, wherein a concentration ofDMSO is about 5 weight percent of the formulation.
 12. The formulationof claim 1, wherein said carrier further comprises at least onepenetration enhancer and said at least one penetration enhancer isselected from the group consisting of propylene glycol (PG), dimethylformamide (DMF), allantoin, urazole, N,N-dimethylacetamide (DMA),decylmethylsulfoxide (C₁₀ MSO), polyethylene glycol monolaurate (PEGML),propylene glycol monolaurate (PGML), Phosal, glycerol monolaurate (GML),lecithin, 1-substituted azacycloheptan-2-ones, alcohols, vegetable oil,phosphatidylcholine concentrate (PC), and mixtures thereof.
 13. Theformulation of claim 10, wherein said carrier further comprises at leastone surfactant.
 14. The formulation of claim 13, wherein a concentrationof said at least one surfactant ranges from about 1 weight percent toabout 10 weight percent.
 15. The formulation of claim 13, wherein saidat least one surfactant is selected from the group consisting ofnon-ionic surfactant, anionic surfactant, cationic surfactant andamphiphilic surfactant.
 16. The formulation of claim 15, wherein saidsurfactant is selected from the group consisting of polyoxyethylenesorbitan monolaurate, octoxynol, tyloxapol, nonionic polyoxyethylenesurfactants, sorbitan mono-octadecenoate, poloxamers and emulphors. 17.The formulation of claim 1, further comprising an additional activeagent.
 18. The formulation of claim 17, wherein said additional activeagent is selected from the group consisting of an antibiotic agent, anantimicrobial agent, an anti-acne agent, an antibacterial agent, anantifungal agent, an antiviral agent, a steroidal anti-inflammatoryagent, a non-steroidal anti-inflammatory agent, an anesthetic agent, anantipruriginous agent, an antiprotozoal agent, an anti-oxidant, achemotherapeutic agent, an antidepressant, an antihistamine, a vitamin,a hormone, a keratolytic agent and an antidandruff agent.
 19. Theformulation of claim 1, wherein a concentration of saidtellurium-containing compound ranges from about 15 weight percent toabout 20 weight percent.
 20. The formulation of claim 1, wherein saidtellurium-containing compound has general Formula I.
 21. The formulationof claim 20, wherein t, u and v are each
 0. 22. The formulation of claim21, wherein R₁, R₈, R₉ and R₁₀ are each hydrogen.
 23. The formulation ofclaim 22, wherein X is chloro.
 24. The formulation of claim 23, whereinY is selected from the group consisting of ammonium, phosphonium,potassium, sodium and lithium.
 25. The formulation of claim 1, being ahydrophilic formulation.
 26. The formulation of claim 1, being awashable formulation.
 27. The formulation of claim 1, having a viscosityin the range of from about 1,000 cpi to about 1,000,000 cpi at roomtemperature.
 28. The formulation of claim 1, having a viscosity in therange of from about 3,000 cpi to about 30,000 cpi at room temperature.29. The formulation of claim 1, being packaged in a packaging materialand identified in print, in or on the packaging material, for use in thetreatment of medical condition in which topical application of saidtellurium-containing compound is beneficial, wherein said medicalcondition is selected from the group consisting of scleroderma,psoriasis, atopic dermatitis, scarring, alopecia, hair loss, metastaticmelanoma, basal cell carcinoma, actinic keratosis and UV skin damage.30. The formulation of claim 1, being in a form selected from the groupconsisting of a cream, an ointment, a paste, a gel, a lotion, a milk, asuspension, a solution, an aerosol, a spray, a foam, a shampoo, amousse, a serum, a swab, a pledget, a pad, a tincture, a patch and asoap.
 31. A method of treating a condition in which topical applicationof a tellurium-containing compound is beneficial, the method comprisingadministering to a subject in need thereof a therapeutically effectiveamount of the formulation of claim
 1. 32. The method of claim 31,wherein said condition is selected from the group consisting ofscleroderma, psoriasis, atopic dermatitis, scarring, alopecia, hairloss, metastatic melanoma, basal cell carcinoma, actinic keratosis andUV skin damage.
 33. A process of preparing the formulation of claim 1,the process comprising mixing said tellurium-containing compound andsaid carrier.
 34. The process of claim 33, wherein said mixing isconducted at a temperature that ranges from about 10° C. to about 100°C.
 35. A highly stable formulation for topical application comprising atellurium-containing compound having at least one tellurium dioxomoiety, the tellurium-containing compound selected from AS101 and SAS,the tellurium-containing compound in an amount of about 10 to about 35weight percent of the formulation, a carrier comprising DMSO anddiethylene glycol monoethyl ether, the carrier selected such that: saidtellurium-containing compound, at a concentration of 10 weight percent,is soluble, dispersible and/or suspendable in the carrier; and theformulation is chemically and physically stable upon storage at roomtemperature for at least 30 days.
 36. The formulation of claim 35,wherein the tellurium-containing compound comprises about 15 weightpercent of the formulation.
 37. The formulation of claim 36, wherein thetellurium-containing compound is AS101.
 38. The formulation of claim 35,further comprising propylene glycol.
 39. The formulation of claim 35further comprising DMSO in an amount by weight percent of at least about5%.
 40. The formulation of claim 39, further comprising propyleneglycol.
 41. The formulation of claim 1, wherein saidtellurium-containing compound is a compound of formula (I).
 42. Theformulation of claim 1, wherein said tellurium-containing compound isthe sole active ingredient in the formulation.